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Ultraprocessed Foods Linked to Faster Biological Aging
TOPLINE:
and factors other than poor nutritional content may be to blame.
METHODOLOGY:
- Previous studies have reported an association between high consumption of UPFs and some measures of early biological aging, such as shorter telomere length, cognitive decline, and frailty, but the relationship is largely unexplored so far, including exactly how UPFs may harm health.
- To examine the association between UPF consumption and biological aging, researchers conducted a cross-sectional analysis of 22,495 participants (mean chronological age, 55.6 years; 52% women) from the Moli-sani Study in Italy, who were recruited between 2005 and 2010.
- Food intake was assessed with a food frequency questionnaire that covered 188 different food items, each of which was categorized into one of four groups based on the extent of processing, ranging from minimally processed foods, such as fruits, vegetables, meat and fish, to UPFs.
- UPF intake was determined by weight, using the ratio of UPFs to the total weight of food and beverages (g/d), and participants were categorized into sex-specific fifths according to the proportion of UPFs in their total food intake. Diet quality was also evaluated using the Mediterranean Diet Score.
- Biological age was computed using a deep neural network approach based on 36 circulating blood biomarkers, and the mean difference between the mean biological and chronological ages was analyzed.
TAKEAWAY:
- The mean difference between biological and chronological ages of the participants was –0.70 years.
- Higher intake of UPFs was associated with accelerated biological aging compared with the lowest intake (regression coefficient, 0.34; 95% CI, 0.08-0.61), with a mean difference between the biological and chronological ages of −4.1 years and 1.6 years in those with the lowest and highest intakes, respectively.
- The association between UPF consumption and biological aging was nonlinear (P = .049 for nonlinearity). The association tended to be stronger in men than in women, but this was not statistically significant.
- Including the Mediterranean Diet Score in the model slightly attenuated the association by 9.1%, indicating that poor nutritional content was likely to explain a small part of the underlying mechanism.
IN PRACTICE:
“Our results showed that the UPFs–biological aging association was weakly explained by the poor nutritional composition of these highly processed foods, suggesting that biological aging could be mainly influenced by non-nutrient food characteristics, which include altered food matrix, contact materials and neo-formed compounds,” the authors wrote.
SOURCE:
The study was led by Simona Esposito, Research Unit of Epidemiology and Prevention, IRCCS Neuromed, Isernia, Italy. It was published online in The American Journal of Clinical Nutrition.
LIMITATIONS:
The cross-sectional design of the study limited the ability to determine the temporal directionality of the association, and the observational nature of the study limited the ability to establish the causality between UPF consumption and biological aging. The use of self-reported dietary data may have introduced recall bias. The study population was limited to adults from Central-Southern Italy, which may affect the generalizability of the findings.
DISCLOSURES:
The study was developed within the project funded by the Next Generation European Union “Age-It — Ageing well in an ageing society” project, National Recovery and Resilience Plan. The analyses were partially supported by the Italian Ministry of Health. The authors declared no conflicts of interest.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
TOPLINE:
and factors other than poor nutritional content may be to blame.
METHODOLOGY:
- Previous studies have reported an association between high consumption of UPFs and some measures of early biological aging, such as shorter telomere length, cognitive decline, and frailty, but the relationship is largely unexplored so far, including exactly how UPFs may harm health.
- To examine the association between UPF consumption and biological aging, researchers conducted a cross-sectional analysis of 22,495 participants (mean chronological age, 55.6 years; 52% women) from the Moli-sani Study in Italy, who were recruited between 2005 and 2010.
- Food intake was assessed with a food frequency questionnaire that covered 188 different food items, each of which was categorized into one of four groups based on the extent of processing, ranging from minimally processed foods, such as fruits, vegetables, meat and fish, to UPFs.
- UPF intake was determined by weight, using the ratio of UPFs to the total weight of food and beverages (g/d), and participants were categorized into sex-specific fifths according to the proportion of UPFs in their total food intake. Diet quality was also evaluated using the Mediterranean Diet Score.
- Biological age was computed using a deep neural network approach based on 36 circulating blood biomarkers, and the mean difference between the mean biological and chronological ages was analyzed.
TAKEAWAY:
- The mean difference between biological and chronological ages of the participants was –0.70 years.
- Higher intake of UPFs was associated with accelerated biological aging compared with the lowest intake (regression coefficient, 0.34; 95% CI, 0.08-0.61), with a mean difference between the biological and chronological ages of −4.1 years and 1.6 years in those with the lowest and highest intakes, respectively.
- The association between UPF consumption and biological aging was nonlinear (P = .049 for nonlinearity). The association tended to be stronger in men than in women, but this was not statistically significant.
- Including the Mediterranean Diet Score in the model slightly attenuated the association by 9.1%, indicating that poor nutritional content was likely to explain a small part of the underlying mechanism.
IN PRACTICE:
“Our results showed that the UPFs–biological aging association was weakly explained by the poor nutritional composition of these highly processed foods, suggesting that biological aging could be mainly influenced by non-nutrient food characteristics, which include altered food matrix, contact materials and neo-formed compounds,” the authors wrote.
SOURCE:
The study was led by Simona Esposito, Research Unit of Epidemiology and Prevention, IRCCS Neuromed, Isernia, Italy. It was published online in The American Journal of Clinical Nutrition.
LIMITATIONS:
The cross-sectional design of the study limited the ability to determine the temporal directionality of the association, and the observational nature of the study limited the ability to establish the causality between UPF consumption and biological aging. The use of self-reported dietary data may have introduced recall bias. The study population was limited to adults from Central-Southern Italy, which may affect the generalizability of the findings.
DISCLOSURES:
The study was developed within the project funded by the Next Generation European Union “Age-It — Ageing well in an ageing society” project, National Recovery and Resilience Plan. The analyses were partially supported by the Italian Ministry of Health. The authors declared no conflicts of interest.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
TOPLINE:
and factors other than poor nutritional content may be to blame.
METHODOLOGY:
- Previous studies have reported an association between high consumption of UPFs and some measures of early biological aging, such as shorter telomere length, cognitive decline, and frailty, but the relationship is largely unexplored so far, including exactly how UPFs may harm health.
- To examine the association between UPF consumption and biological aging, researchers conducted a cross-sectional analysis of 22,495 participants (mean chronological age, 55.6 years; 52% women) from the Moli-sani Study in Italy, who were recruited between 2005 and 2010.
- Food intake was assessed with a food frequency questionnaire that covered 188 different food items, each of which was categorized into one of four groups based on the extent of processing, ranging from minimally processed foods, such as fruits, vegetables, meat and fish, to UPFs.
- UPF intake was determined by weight, using the ratio of UPFs to the total weight of food and beverages (g/d), and participants were categorized into sex-specific fifths according to the proportion of UPFs in their total food intake. Diet quality was also evaluated using the Mediterranean Diet Score.
- Biological age was computed using a deep neural network approach based on 36 circulating blood biomarkers, and the mean difference between the mean biological and chronological ages was analyzed.
TAKEAWAY:
- The mean difference between biological and chronological ages of the participants was –0.70 years.
- Higher intake of UPFs was associated with accelerated biological aging compared with the lowest intake (regression coefficient, 0.34; 95% CI, 0.08-0.61), with a mean difference between the biological and chronological ages of −4.1 years and 1.6 years in those with the lowest and highest intakes, respectively.
- The association between UPF consumption and biological aging was nonlinear (P = .049 for nonlinearity). The association tended to be stronger in men than in women, but this was not statistically significant.
- Including the Mediterranean Diet Score in the model slightly attenuated the association by 9.1%, indicating that poor nutritional content was likely to explain a small part of the underlying mechanism.
IN PRACTICE:
“Our results showed that the UPFs–biological aging association was weakly explained by the poor nutritional composition of these highly processed foods, suggesting that biological aging could be mainly influenced by non-nutrient food characteristics, which include altered food matrix, contact materials and neo-formed compounds,” the authors wrote.
SOURCE:
The study was led by Simona Esposito, Research Unit of Epidemiology and Prevention, IRCCS Neuromed, Isernia, Italy. It was published online in The American Journal of Clinical Nutrition.
LIMITATIONS:
The cross-sectional design of the study limited the ability to determine the temporal directionality of the association, and the observational nature of the study limited the ability to establish the causality between UPF consumption and biological aging. The use of self-reported dietary data may have introduced recall bias. The study population was limited to adults from Central-Southern Italy, which may affect the generalizability of the findings.
DISCLOSURES:
The study was developed within the project funded by the Next Generation European Union “Age-It — Ageing well in an ageing society” project, National Recovery and Resilience Plan. The analyses were partially supported by the Italian Ministry of Health. The authors declared no conflicts of interest.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
An Epidemiologist’s Guide to Debunking Nutritional Research
You’re invited to a dinner party but you struggle to make small talk. Do not worry; that will invariably crop up over cocktails. Because all journalism has been reduced to listicles, here are four ways to seem clever at dinner parties.
1. The Predinner Cocktails: A Lesson in Reverse Causation
Wine connoisseurs sniff, swirl, and gently swish the wine in their mouths before spitting out and cleansing their palates to better appreciate the subtlety of each vintage. If you’re not an oenophile, no matter. Whenever somebody claims that moderate amounts of alcohol are good for your heart, this is your moment to pounce. Interject yourself in the conversation and tell everybody about reverse causation.
Reverse causation, also known as protopathic bias, involves misinterpreting the directionality of an association. You assume that X leads to Y, when in fact Y leads to X. Temporal paradoxes are useful plot devices in science fiction movies, but they have no place in medical research. In our bland world, cause must precede effect. As such, smoking leads to lung cancer; lung cancer doesn’t make you smoke more.
But with alcohol, directionality is less obvious. Many studies of alcohol and cardiovascular disease have demonstrated a U-shaped association, with risk being lowest among those who drink moderate amounts of alcohol (usually one to two drinks per day) and higher in those who drink more and also those who drink very little.
But one must ask why some people drink little or no alcohol. There is an important difference between former drinkers and never drinkers. Former drinkers cut back for a reason. More likely than not, the reason for this newfound sobriety was medical. A new cancer diagnosis, the emergence of atrial fibrillation, the development of diabetes, or rising blood pressure are all good reasons to reduce or eliminate alcohol. A cross-sectional study will fail to capture that alcohol consumption changes over time — people who now don’t drink may have imbibed alcohol in years past. It was not abstinence that led to an increased risk for heart disease; it was the increased risk for heart disease that led to abstinence.
You see the same phenomenon with the so-called obesity paradox. The idea that being a little overweight is good for you may appeal when you no longer fit into last year’s pants. But people who are underweight are so for a reason. Malnutrition, cachexia from cancer, or some other cause is almost certainly driving up the risk at the left-hand side of the U-shaped curve that makes the middle part seem better than it actually is.
Food consumption changes over time. A cross-sectional survey at one point in time cannot accurately capture past habits and distant exposures, especially for diseases such as heart disease and cancer that develop slowly over time. Studies on alcohol that try to overcome these shortcomings by eliminating former drinkers, or by using Mendelian randomization to better account for past exposure, do not show a cardiovascular benefit for moderate red wine drinking.
2. The Hors D’oeuvres — The Importance of RCTs
Now that you have made yourself the center of attention, it is time to cement your newfound reputation as a font of scientific knowledge. Most self-respecting hosts will serve smoked salmon as an amuse-bouche before the main meal. When someone mentions the health benefits of fish oils, you should take the opportunity to teach them about confounding.
Fish, especially cold-water fish from northern climates, have relatively high amounts of omega-3 fatty acids. Despite the plethora of observational studies suggesting a cardiovascular benefit, it’s now relatively clear that fish oil or omega-3 supplements have no medical benefit.
This will probably come as a shock to the worried well, but many studies, including VITAL and ASCEND, have demonstrated no cardiovascular or cancer benefit to supplementation with omega-3s. The reason is straightforward and explains why hormone replacement therapy, vitamin D, and myriad purported game-changers never panned out. Confounding is hard to overcome in observational research.
Prior to the publication of the Women’s Health Initiative (WHI) Study, hormone replacement therapy was routinely prescribed to postmenopausal women because numerous observational studies suggested a cardiovascular benefit. But with the publication of the WHI study, it became clear that much of that “benefit” was due to confounding. The women choosing to take hormones were more health conscious at baseline and healthier overall.
A similar phenomenon occurred during COVID. Patients with low serum vitamin D levels had worse outcomes, prompting many to suggest vitamin D supplementation as a possible treatment. Trials did not support the intervention because we’d overlooked the obvious. People with vitamin D deficiency have underlying health problems that contribute to the vitamin D deficiency. They are probably older, frailer, possibly with a poorer diet. No amount of statistical adjustment can account for all those differences, and some degree of residual confounding will always persist.
The only way to overcome confounding is with randomization. When patients are randomly assigned to one group or another, their baseline differences largely balance out if the randomization was performed properly and the groups were large enough. There is a role for observational research, such as in situations where ethics, cost, and practicality do not allow for a randomized controlled trial. But randomized controlled trials have largely put to rest the purported health benefits of over-the-counter fish oils, omega-3s, and vitamin D.
3. The Main Course — Absolute vs Relative Risk
When you get to the main course, all eyes will now be on you. You will almost certainly be called upon to pronounce on the harms or benefits of red meat consumption. Begin by regaling your guests with a little trivia. Ask them if they know the definition of red meat and white meat. When someone says pork is white meat, you can reveal that “pork, the other white meat,” was a marketing slogan with no scientific underpinning. Now that everyone is lulled into a stupefied silence, tell them that red meat comes from mammals and white meat comes from birds. As they process this revelation, you can now launch into the deeply mathematical concept of absolute vs relative risk.
Many etiquette books will caution against bringing up math at a dinner party. These books are wrong. Everyone finds math interesting if they are primed properly. For example, you can point to a study claiming that berries reduce cardiovascular risk in women. Even if true — and there is reason to be cautious, given the observational nature of the research — we need to understand what the authors meant by a 32% risk reduction. (Side note: It was a reduction in hazard, with a hazard ratio of 0.68 (95% CI, 0.49-0.96), but we won’t dwell on the difference between hazard ratios and risk ratios right now.)
This relative risk reduction has to be interpreted carefully. The authors divided the population into quintiles based on their consumption of anthocyanins (the antioxidant in blueberries and strawberries) and compared the bottom fifth (average consumption, 2.5 mg/d) with the top fifth (average consumption, 25 mg/d). The bottom quintile had 126 myocardial infarctions (MIs) over 324,793 patient-years compared with 59 MIs over 332,143 patient-years. Some quick math shows an approximate reduction from 39 to 18 MIs per 100,000 patient-years. Or to put it another way, you must get 4762 women to increase their berry consumption 10-fold for 1 year to prevent one heart attack. Feel free to show people how you calculated this number. They will be impressed by your head for numbers. It is nothing more than 39 minus 18, divided by 100,000, to get the absolute risk reduction. Take the reciprocal of this (ie, 1 divided by this number) to get the number needed to treat.
Describing risks in absolute terms or using number needed to treat (or harm) can help conceptualize statistics that are sometimes hard to wrap your head around.
4. Dessert — Funding
By the time the coffee is served, everyone will be hanging on to your every word. This is as it should be, and you should not be afraid of your newfound power and influence.
Dessert will probably involve some form of chocolate, possibly in cake format. (Anyone who serves fruit as dessert is not someone you should associate with.) Take the opportunity to tell your follow diners that chocolate is not actually good for you and will not boost brain performance.
The health benefits of chocolate are often repeated but rarely scrutinized. In fact, much of the scientific research purporting to show that chocolate is good for you did not actually study chocolate. It usually involved a cocoa bean extract because the chocolate manufacturing process destroys the supposedly health-promoting antioxidants in the cocoa bean. It is true that dark chocolate has more antioxidants than milk chocolate, and that the addition of milk to chocolate further inactivates the potentially healthy antioxidants. But the amount of sugar and fat that has to be added to chocolate to make it palatable precludes any serious consideration about health benefits. Dark chocolate may have less fat and sugar than milk chocolate, but it still has a lot.
But even the cocoa bean extract doesn’t seem to do much for your heart or your brain. The long-awaited COSMOS study was published with surprisingly little fanfare. The largest randomized controlled trial of chocolate (or rather cocoa bean extract) was supposed to settle the issue definitively.
COSMOS showed no cardiovascular or neurocognitive benefit to the cocoa bean extract. But the health halo of chocolate continues to be bolstered by many studies funded by chocolate manufacturers.
We are appropriately critical of the pharmaceutical industry’s involvement in drug research. However, we should not forget that any private entity is prone to the same self-interest regardless of its product’s tastiness. How many of you knew that there was an avocado lobby funding research? No matter how many industry-funded observational studies using surrogate endpoints are out there telling you that chocolate is healthy, a randomized trial with hard clinical endpoints such as COSMOS should generally win the day.
The Final Goodbyes — Summarizing Your Case
As the party slowly winds down and everyone is saddened that you will soon take your leave, synthesize everything you have taught them over the evening. Like movies, not all studies are good. Some are just bad. They can be prone to reverse causation or confounding, and they may report relative risks when absolute risks would be more telling. Reading research studies critically is essential for separating the wheat from the chaff. With the knowledge you have now imparted to your friends, they will be much better consumers of medical news, especially when it comes to food.
And they will no doubt thank you for it by never inviting you to another dinner party!
Labos, a cardiologist at Hôpital, Notre-Dame, Montreal, Quebec, Canada, has disclosed no relevant financial relationships. He has a degree in epidemiology.
A version of this article appeared on Medscape.com.
You’re invited to a dinner party but you struggle to make small talk. Do not worry; that will invariably crop up over cocktails. Because all journalism has been reduced to listicles, here are four ways to seem clever at dinner parties.
1. The Predinner Cocktails: A Lesson in Reverse Causation
Wine connoisseurs sniff, swirl, and gently swish the wine in their mouths before spitting out and cleansing their palates to better appreciate the subtlety of each vintage. If you’re not an oenophile, no matter. Whenever somebody claims that moderate amounts of alcohol are good for your heart, this is your moment to pounce. Interject yourself in the conversation and tell everybody about reverse causation.
Reverse causation, also known as protopathic bias, involves misinterpreting the directionality of an association. You assume that X leads to Y, when in fact Y leads to X. Temporal paradoxes are useful plot devices in science fiction movies, but they have no place in medical research. In our bland world, cause must precede effect. As such, smoking leads to lung cancer; lung cancer doesn’t make you smoke more.
But with alcohol, directionality is less obvious. Many studies of alcohol and cardiovascular disease have demonstrated a U-shaped association, with risk being lowest among those who drink moderate amounts of alcohol (usually one to two drinks per day) and higher in those who drink more and also those who drink very little.
But one must ask why some people drink little or no alcohol. There is an important difference between former drinkers and never drinkers. Former drinkers cut back for a reason. More likely than not, the reason for this newfound sobriety was medical. A new cancer diagnosis, the emergence of atrial fibrillation, the development of diabetes, or rising blood pressure are all good reasons to reduce or eliminate alcohol. A cross-sectional study will fail to capture that alcohol consumption changes over time — people who now don’t drink may have imbibed alcohol in years past. It was not abstinence that led to an increased risk for heart disease; it was the increased risk for heart disease that led to abstinence.
You see the same phenomenon with the so-called obesity paradox. The idea that being a little overweight is good for you may appeal when you no longer fit into last year’s pants. But people who are underweight are so for a reason. Malnutrition, cachexia from cancer, or some other cause is almost certainly driving up the risk at the left-hand side of the U-shaped curve that makes the middle part seem better than it actually is.
Food consumption changes over time. A cross-sectional survey at one point in time cannot accurately capture past habits and distant exposures, especially for diseases such as heart disease and cancer that develop slowly over time. Studies on alcohol that try to overcome these shortcomings by eliminating former drinkers, or by using Mendelian randomization to better account for past exposure, do not show a cardiovascular benefit for moderate red wine drinking.
2. The Hors D’oeuvres — The Importance of RCTs
Now that you have made yourself the center of attention, it is time to cement your newfound reputation as a font of scientific knowledge. Most self-respecting hosts will serve smoked salmon as an amuse-bouche before the main meal. When someone mentions the health benefits of fish oils, you should take the opportunity to teach them about confounding.
Fish, especially cold-water fish from northern climates, have relatively high amounts of omega-3 fatty acids. Despite the plethora of observational studies suggesting a cardiovascular benefit, it’s now relatively clear that fish oil or omega-3 supplements have no medical benefit.
This will probably come as a shock to the worried well, but many studies, including VITAL and ASCEND, have demonstrated no cardiovascular or cancer benefit to supplementation with omega-3s. The reason is straightforward and explains why hormone replacement therapy, vitamin D, and myriad purported game-changers never panned out. Confounding is hard to overcome in observational research.
Prior to the publication of the Women’s Health Initiative (WHI) Study, hormone replacement therapy was routinely prescribed to postmenopausal women because numerous observational studies suggested a cardiovascular benefit. But with the publication of the WHI study, it became clear that much of that “benefit” was due to confounding. The women choosing to take hormones were more health conscious at baseline and healthier overall.
A similar phenomenon occurred during COVID. Patients with low serum vitamin D levels had worse outcomes, prompting many to suggest vitamin D supplementation as a possible treatment. Trials did not support the intervention because we’d overlooked the obvious. People with vitamin D deficiency have underlying health problems that contribute to the vitamin D deficiency. They are probably older, frailer, possibly with a poorer diet. No amount of statistical adjustment can account for all those differences, and some degree of residual confounding will always persist.
The only way to overcome confounding is with randomization. When patients are randomly assigned to one group or another, their baseline differences largely balance out if the randomization was performed properly and the groups were large enough. There is a role for observational research, such as in situations where ethics, cost, and practicality do not allow for a randomized controlled trial. But randomized controlled trials have largely put to rest the purported health benefits of over-the-counter fish oils, omega-3s, and vitamin D.
3. The Main Course — Absolute vs Relative Risk
When you get to the main course, all eyes will now be on you. You will almost certainly be called upon to pronounce on the harms or benefits of red meat consumption. Begin by regaling your guests with a little trivia. Ask them if they know the definition of red meat and white meat. When someone says pork is white meat, you can reveal that “pork, the other white meat,” was a marketing slogan with no scientific underpinning. Now that everyone is lulled into a stupefied silence, tell them that red meat comes from mammals and white meat comes from birds. As they process this revelation, you can now launch into the deeply mathematical concept of absolute vs relative risk.
Many etiquette books will caution against bringing up math at a dinner party. These books are wrong. Everyone finds math interesting if they are primed properly. For example, you can point to a study claiming that berries reduce cardiovascular risk in women. Even if true — and there is reason to be cautious, given the observational nature of the research — we need to understand what the authors meant by a 32% risk reduction. (Side note: It was a reduction in hazard, with a hazard ratio of 0.68 (95% CI, 0.49-0.96), but we won’t dwell on the difference between hazard ratios and risk ratios right now.)
This relative risk reduction has to be interpreted carefully. The authors divided the population into quintiles based on their consumption of anthocyanins (the antioxidant in blueberries and strawberries) and compared the bottom fifth (average consumption, 2.5 mg/d) with the top fifth (average consumption, 25 mg/d). The bottom quintile had 126 myocardial infarctions (MIs) over 324,793 patient-years compared with 59 MIs over 332,143 patient-years. Some quick math shows an approximate reduction from 39 to 18 MIs per 100,000 patient-years. Or to put it another way, you must get 4762 women to increase their berry consumption 10-fold for 1 year to prevent one heart attack. Feel free to show people how you calculated this number. They will be impressed by your head for numbers. It is nothing more than 39 minus 18, divided by 100,000, to get the absolute risk reduction. Take the reciprocal of this (ie, 1 divided by this number) to get the number needed to treat.
Describing risks in absolute terms or using number needed to treat (or harm) can help conceptualize statistics that are sometimes hard to wrap your head around.
4. Dessert — Funding
By the time the coffee is served, everyone will be hanging on to your every word. This is as it should be, and you should not be afraid of your newfound power and influence.
Dessert will probably involve some form of chocolate, possibly in cake format. (Anyone who serves fruit as dessert is not someone you should associate with.) Take the opportunity to tell your follow diners that chocolate is not actually good for you and will not boost brain performance.
The health benefits of chocolate are often repeated but rarely scrutinized. In fact, much of the scientific research purporting to show that chocolate is good for you did not actually study chocolate. It usually involved a cocoa bean extract because the chocolate manufacturing process destroys the supposedly health-promoting antioxidants in the cocoa bean. It is true that dark chocolate has more antioxidants than milk chocolate, and that the addition of milk to chocolate further inactivates the potentially healthy antioxidants. But the amount of sugar and fat that has to be added to chocolate to make it palatable precludes any serious consideration about health benefits. Dark chocolate may have less fat and sugar than milk chocolate, but it still has a lot.
But even the cocoa bean extract doesn’t seem to do much for your heart or your brain. The long-awaited COSMOS study was published with surprisingly little fanfare. The largest randomized controlled trial of chocolate (or rather cocoa bean extract) was supposed to settle the issue definitively.
COSMOS showed no cardiovascular or neurocognitive benefit to the cocoa bean extract. But the health halo of chocolate continues to be bolstered by many studies funded by chocolate manufacturers.
We are appropriately critical of the pharmaceutical industry’s involvement in drug research. However, we should not forget that any private entity is prone to the same self-interest regardless of its product’s tastiness. How many of you knew that there was an avocado lobby funding research? No matter how many industry-funded observational studies using surrogate endpoints are out there telling you that chocolate is healthy, a randomized trial with hard clinical endpoints such as COSMOS should generally win the day.
The Final Goodbyes — Summarizing Your Case
As the party slowly winds down and everyone is saddened that you will soon take your leave, synthesize everything you have taught them over the evening. Like movies, not all studies are good. Some are just bad. They can be prone to reverse causation or confounding, and they may report relative risks when absolute risks would be more telling. Reading research studies critically is essential for separating the wheat from the chaff. With the knowledge you have now imparted to your friends, they will be much better consumers of medical news, especially when it comes to food.
And they will no doubt thank you for it by never inviting you to another dinner party!
Labos, a cardiologist at Hôpital, Notre-Dame, Montreal, Quebec, Canada, has disclosed no relevant financial relationships. He has a degree in epidemiology.
A version of this article appeared on Medscape.com.
You’re invited to a dinner party but you struggle to make small talk. Do not worry; that will invariably crop up over cocktails. Because all journalism has been reduced to listicles, here are four ways to seem clever at dinner parties.
1. The Predinner Cocktails: A Lesson in Reverse Causation
Wine connoisseurs sniff, swirl, and gently swish the wine in their mouths before spitting out and cleansing their palates to better appreciate the subtlety of each vintage. If you’re not an oenophile, no matter. Whenever somebody claims that moderate amounts of alcohol are good for your heart, this is your moment to pounce. Interject yourself in the conversation and tell everybody about reverse causation.
Reverse causation, also known as protopathic bias, involves misinterpreting the directionality of an association. You assume that X leads to Y, when in fact Y leads to X. Temporal paradoxes are useful plot devices in science fiction movies, but they have no place in medical research. In our bland world, cause must precede effect. As such, smoking leads to lung cancer; lung cancer doesn’t make you smoke more.
But with alcohol, directionality is less obvious. Many studies of alcohol and cardiovascular disease have demonstrated a U-shaped association, with risk being lowest among those who drink moderate amounts of alcohol (usually one to two drinks per day) and higher in those who drink more and also those who drink very little.
But one must ask why some people drink little or no alcohol. There is an important difference between former drinkers and never drinkers. Former drinkers cut back for a reason. More likely than not, the reason for this newfound sobriety was medical. A new cancer diagnosis, the emergence of atrial fibrillation, the development of diabetes, or rising blood pressure are all good reasons to reduce or eliminate alcohol. A cross-sectional study will fail to capture that alcohol consumption changes over time — people who now don’t drink may have imbibed alcohol in years past. It was not abstinence that led to an increased risk for heart disease; it was the increased risk for heart disease that led to abstinence.
You see the same phenomenon with the so-called obesity paradox. The idea that being a little overweight is good for you may appeal when you no longer fit into last year’s pants. But people who are underweight are so for a reason. Malnutrition, cachexia from cancer, or some other cause is almost certainly driving up the risk at the left-hand side of the U-shaped curve that makes the middle part seem better than it actually is.
Food consumption changes over time. A cross-sectional survey at one point in time cannot accurately capture past habits and distant exposures, especially for diseases such as heart disease and cancer that develop slowly over time. Studies on alcohol that try to overcome these shortcomings by eliminating former drinkers, or by using Mendelian randomization to better account for past exposure, do not show a cardiovascular benefit for moderate red wine drinking.
2. The Hors D’oeuvres — The Importance of RCTs
Now that you have made yourself the center of attention, it is time to cement your newfound reputation as a font of scientific knowledge. Most self-respecting hosts will serve smoked salmon as an amuse-bouche before the main meal. When someone mentions the health benefits of fish oils, you should take the opportunity to teach them about confounding.
Fish, especially cold-water fish from northern climates, have relatively high amounts of omega-3 fatty acids. Despite the plethora of observational studies suggesting a cardiovascular benefit, it’s now relatively clear that fish oil or omega-3 supplements have no medical benefit.
This will probably come as a shock to the worried well, but many studies, including VITAL and ASCEND, have demonstrated no cardiovascular or cancer benefit to supplementation with omega-3s. The reason is straightforward and explains why hormone replacement therapy, vitamin D, and myriad purported game-changers never panned out. Confounding is hard to overcome in observational research.
Prior to the publication of the Women’s Health Initiative (WHI) Study, hormone replacement therapy was routinely prescribed to postmenopausal women because numerous observational studies suggested a cardiovascular benefit. But with the publication of the WHI study, it became clear that much of that “benefit” was due to confounding. The women choosing to take hormones were more health conscious at baseline and healthier overall.
A similar phenomenon occurred during COVID. Patients with low serum vitamin D levels had worse outcomes, prompting many to suggest vitamin D supplementation as a possible treatment. Trials did not support the intervention because we’d overlooked the obvious. People with vitamin D deficiency have underlying health problems that contribute to the vitamin D deficiency. They are probably older, frailer, possibly with a poorer diet. No amount of statistical adjustment can account for all those differences, and some degree of residual confounding will always persist.
The only way to overcome confounding is with randomization. When patients are randomly assigned to one group or another, their baseline differences largely balance out if the randomization was performed properly and the groups were large enough. There is a role for observational research, such as in situations where ethics, cost, and practicality do not allow for a randomized controlled trial. But randomized controlled trials have largely put to rest the purported health benefits of over-the-counter fish oils, omega-3s, and vitamin D.
3. The Main Course — Absolute vs Relative Risk
When you get to the main course, all eyes will now be on you. You will almost certainly be called upon to pronounce on the harms or benefits of red meat consumption. Begin by regaling your guests with a little trivia. Ask them if they know the definition of red meat and white meat. When someone says pork is white meat, you can reveal that “pork, the other white meat,” was a marketing slogan with no scientific underpinning. Now that everyone is lulled into a stupefied silence, tell them that red meat comes from mammals and white meat comes from birds. As they process this revelation, you can now launch into the deeply mathematical concept of absolute vs relative risk.
Many etiquette books will caution against bringing up math at a dinner party. These books are wrong. Everyone finds math interesting if they are primed properly. For example, you can point to a study claiming that berries reduce cardiovascular risk in women. Even if true — and there is reason to be cautious, given the observational nature of the research — we need to understand what the authors meant by a 32% risk reduction. (Side note: It was a reduction in hazard, with a hazard ratio of 0.68 (95% CI, 0.49-0.96), but we won’t dwell on the difference between hazard ratios and risk ratios right now.)
This relative risk reduction has to be interpreted carefully. The authors divided the population into quintiles based on their consumption of anthocyanins (the antioxidant in blueberries and strawberries) and compared the bottom fifth (average consumption, 2.5 mg/d) with the top fifth (average consumption, 25 mg/d). The bottom quintile had 126 myocardial infarctions (MIs) over 324,793 patient-years compared with 59 MIs over 332,143 patient-years. Some quick math shows an approximate reduction from 39 to 18 MIs per 100,000 patient-years. Or to put it another way, you must get 4762 women to increase their berry consumption 10-fold for 1 year to prevent one heart attack. Feel free to show people how you calculated this number. They will be impressed by your head for numbers. It is nothing more than 39 minus 18, divided by 100,000, to get the absolute risk reduction. Take the reciprocal of this (ie, 1 divided by this number) to get the number needed to treat.
Describing risks in absolute terms or using number needed to treat (or harm) can help conceptualize statistics that are sometimes hard to wrap your head around.
4. Dessert — Funding
By the time the coffee is served, everyone will be hanging on to your every word. This is as it should be, and you should not be afraid of your newfound power and influence.
Dessert will probably involve some form of chocolate, possibly in cake format. (Anyone who serves fruit as dessert is not someone you should associate with.) Take the opportunity to tell your follow diners that chocolate is not actually good for you and will not boost brain performance.
The health benefits of chocolate are often repeated but rarely scrutinized. In fact, much of the scientific research purporting to show that chocolate is good for you did not actually study chocolate. It usually involved a cocoa bean extract because the chocolate manufacturing process destroys the supposedly health-promoting antioxidants in the cocoa bean. It is true that dark chocolate has more antioxidants than milk chocolate, and that the addition of milk to chocolate further inactivates the potentially healthy antioxidants. But the amount of sugar and fat that has to be added to chocolate to make it palatable precludes any serious consideration about health benefits. Dark chocolate may have less fat and sugar than milk chocolate, but it still has a lot.
But even the cocoa bean extract doesn’t seem to do much for your heart or your brain. The long-awaited COSMOS study was published with surprisingly little fanfare. The largest randomized controlled trial of chocolate (or rather cocoa bean extract) was supposed to settle the issue definitively.
COSMOS showed no cardiovascular or neurocognitive benefit to the cocoa bean extract. But the health halo of chocolate continues to be bolstered by many studies funded by chocolate manufacturers.
We are appropriately critical of the pharmaceutical industry’s involvement in drug research. However, we should not forget that any private entity is prone to the same self-interest regardless of its product’s tastiness. How many of you knew that there was an avocado lobby funding research? No matter how many industry-funded observational studies using surrogate endpoints are out there telling you that chocolate is healthy, a randomized trial with hard clinical endpoints such as COSMOS should generally win the day.
The Final Goodbyes — Summarizing Your Case
As the party slowly winds down and everyone is saddened that you will soon take your leave, synthesize everything you have taught them over the evening. Like movies, not all studies are good. Some are just bad. They can be prone to reverse causation or confounding, and they may report relative risks when absolute risks would be more telling. Reading research studies critically is essential for separating the wheat from the chaff. With the knowledge you have now imparted to your friends, they will be much better consumers of medical news, especially when it comes to food.
And they will no doubt thank you for it by never inviting you to another dinner party!
Labos, a cardiologist at Hôpital, Notre-Dame, Montreal, Quebec, Canada, has disclosed no relevant financial relationships. He has a degree in epidemiology.
A version of this article appeared on Medscape.com.
A Child’s Picky Eating: Normal Phase or Health Concern?
PARIS — “My child is a poor eater” is a complaint frequently heard during medical consultations. Such concerns are often unjustified but a source of much parental frustration.
Marc Bellaïche, MD, a pediatrician at Robert-Debré Hospital in Paris, addressed this issue at France’s annual general medicine conference (JNMG 2024). His presentation focused on distinguishing between parental perception, typical childhood behaviors, and feeding issues that require intervention.
In assessing parental worries, tools such as The Montreal Children’s Hospital Feeding Scale for children aged 6 months to 6 years and the Baby Eating Behavior Questionnaire for those under 6 months can help identify and monitor feeding issues. Observing the child eat, when possible, is also valuable.
Key Phases and Development
Bellaïche focused on children under 6 years, as they frequently experience feeding challenges during critical development phases, such as weaning or when the child is able to sit up.
A phase of neophilia (interest in new foods) typically occurs before 12 months, followed by a phase of neophobia (fear of new foods) between ages 1 and 3 years. This neophobia is a normal part of neuropsychological, sensory, and taste development and can persist if a key developmental moment is marked by a choking incident, mealtime stress, or forced feeding. “Challenges differ between a difficult 3-year-old and a 6- or 7-year-old who still refuses new foods,” he explained.
Parental Pressure and Nutritional Balance
Nutritional balance is essential, but “parental pressure is often too high.” Parents worry because they see food as a “nutraceutical.” Bellaïche recommended defusing anxiety by keeping mealtimes calm, allowing the child to eat at their pace, avoiding force-feeding, keeping meals brief, and avoiding snacks. While “it’s important to stay vigilant — as it’s incorrect to assume a child won’t let themselves starve — most cases can be managed in general practice through parental guidance, empathy, and a positive approach.”
Monitoring growth and weight curves is crucial, with the Kanawati index (ratio of arm circumference to head circumference) being a reliable indicator for specialist referral if < 0.31. A varied diet is important for nutritional balance; when this isn’t achieved, continued consumption of toddler formula after age 3 can prevent iron and calcium deficiencies.
When eating difficulties are documented, healthcare providers should investigate for underlying organic, digestive, or extra-digestive diseases (neurologic, cardiac, renal, etc.). “It’s best not to hastily diagnose cow’s milk protein allergy,” Bellaïche advised, as cases are relatively rare and unnecessarily eliminating milk can complicate a child’s relationship with food. Similarly, gastroesophageal reflux disease should be objectively diagnosed to avoid unnecessary proton pump inhibitor treatment and associated side effects.
For children with low birth weight, mild congenital heart disease, or suggestive dysmorphology, consider evaluating for a genetic syndrome.
Avoidant/Restrictive Food Intake Disorder (ARFID)
ARFID is marked by a lack of interest in food and avoidance due to sensory characteristics. Often observed in anxious children, ARFID is diagnosed in approximately 20% of children with autism spectrum disorder, where food selectivity is prevalent. This condition can hinder a child’s development and may necessitate nutritional supplementation.
Case Profiles in Eating Issues
Bellaïche outlined three typical cases among children considered “picky eaters”:
- The small eater: Often near the lower growth curve limits, this child “grazes and doesn’t sit still.” These children are usually active and have a family history of similar eating habits. Parents should encourage psychomotor activities, discourage snacks outside of mealtimes, and consider fun family picnics on the floor, offering a mezze-style variety of foods.
- The child with a history of trauma: Children with trauma (from intubation, nasogastric tubes, severe vomiting, forced feeding, or choking) may develop aversions requiring behavioral intervention.
- The child with high sensory sensitivity: This child dislikes getting the hands dirty, avoids mouthing objects, or resists certain textures, such as grass and sand. Gradual behavioral approaches with sensory play and visually appealing new foods can be beneficial. Guided self-led food exploration (baby-led weaning) may also help, though dairy intake is often needed to prevent deficiencies during this stage.
Finally, gastroesophageal reflux disease or constipation can contribute to appetite loss. Studies have shown that treating these issues can improve appetite in small eaters.
This story was translated from Univadis France using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
PARIS — “My child is a poor eater” is a complaint frequently heard during medical consultations. Such concerns are often unjustified but a source of much parental frustration.
Marc Bellaïche, MD, a pediatrician at Robert-Debré Hospital in Paris, addressed this issue at France’s annual general medicine conference (JNMG 2024). His presentation focused on distinguishing between parental perception, typical childhood behaviors, and feeding issues that require intervention.
In assessing parental worries, tools such as The Montreal Children’s Hospital Feeding Scale for children aged 6 months to 6 years and the Baby Eating Behavior Questionnaire for those under 6 months can help identify and monitor feeding issues. Observing the child eat, when possible, is also valuable.
Key Phases and Development
Bellaïche focused on children under 6 years, as they frequently experience feeding challenges during critical development phases, such as weaning or when the child is able to sit up.
A phase of neophilia (interest in new foods) typically occurs before 12 months, followed by a phase of neophobia (fear of new foods) between ages 1 and 3 years. This neophobia is a normal part of neuropsychological, sensory, and taste development and can persist if a key developmental moment is marked by a choking incident, mealtime stress, or forced feeding. “Challenges differ between a difficult 3-year-old and a 6- or 7-year-old who still refuses new foods,” he explained.
Parental Pressure and Nutritional Balance
Nutritional balance is essential, but “parental pressure is often too high.” Parents worry because they see food as a “nutraceutical.” Bellaïche recommended defusing anxiety by keeping mealtimes calm, allowing the child to eat at their pace, avoiding force-feeding, keeping meals brief, and avoiding snacks. While “it’s important to stay vigilant — as it’s incorrect to assume a child won’t let themselves starve — most cases can be managed in general practice through parental guidance, empathy, and a positive approach.”
Monitoring growth and weight curves is crucial, with the Kanawati index (ratio of arm circumference to head circumference) being a reliable indicator for specialist referral if < 0.31. A varied diet is important for nutritional balance; when this isn’t achieved, continued consumption of toddler formula after age 3 can prevent iron and calcium deficiencies.
When eating difficulties are documented, healthcare providers should investigate for underlying organic, digestive, or extra-digestive diseases (neurologic, cardiac, renal, etc.). “It’s best not to hastily diagnose cow’s milk protein allergy,” Bellaïche advised, as cases are relatively rare and unnecessarily eliminating milk can complicate a child’s relationship with food. Similarly, gastroesophageal reflux disease should be objectively diagnosed to avoid unnecessary proton pump inhibitor treatment and associated side effects.
For children with low birth weight, mild congenital heart disease, or suggestive dysmorphology, consider evaluating for a genetic syndrome.
Avoidant/Restrictive Food Intake Disorder (ARFID)
ARFID is marked by a lack of interest in food and avoidance due to sensory characteristics. Often observed in anxious children, ARFID is diagnosed in approximately 20% of children with autism spectrum disorder, where food selectivity is prevalent. This condition can hinder a child’s development and may necessitate nutritional supplementation.
Case Profiles in Eating Issues
Bellaïche outlined three typical cases among children considered “picky eaters”:
- The small eater: Often near the lower growth curve limits, this child “grazes and doesn’t sit still.” These children are usually active and have a family history of similar eating habits. Parents should encourage psychomotor activities, discourage snacks outside of mealtimes, and consider fun family picnics on the floor, offering a mezze-style variety of foods.
- The child with a history of trauma: Children with trauma (from intubation, nasogastric tubes, severe vomiting, forced feeding, or choking) may develop aversions requiring behavioral intervention.
- The child with high sensory sensitivity: This child dislikes getting the hands dirty, avoids mouthing objects, or resists certain textures, such as grass and sand. Gradual behavioral approaches with sensory play and visually appealing new foods can be beneficial. Guided self-led food exploration (baby-led weaning) may also help, though dairy intake is often needed to prevent deficiencies during this stage.
Finally, gastroesophageal reflux disease or constipation can contribute to appetite loss. Studies have shown that treating these issues can improve appetite in small eaters.
This story was translated from Univadis France using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
PARIS — “My child is a poor eater” is a complaint frequently heard during medical consultations. Such concerns are often unjustified but a source of much parental frustration.
Marc Bellaïche, MD, a pediatrician at Robert-Debré Hospital in Paris, addressed this issue at France’s annual general medicine conference (JNMG 2024). His presentation focused on distinguishing between parental perception, typical childhood behaviors, and feeding issues that require intervention.
In assessing parental worries, tools such as The Montreal Children’s Hospital Feeding Scale for children aged 6 months to 6 years and the Baby Eating Behavior Questionnaire for those under 6 months can help identify and monitor feeding issues. Observing the child eat, when possible, is also valuable.
Key Phases and Development
Bellaïche focused on children under 6 years, as they frequently experience feeding challenges during critical development phases, such as weaning or when the child is able to sit up.
A phase of neophilia (interest in new foods) typically occurs before 12 months, followed by a phase of neophobia (fear of new foods) between ages 1 and 3 years. This neophobia is a normal part of neuropsychological, sensory, and taste development and can persist if a key developmental moment is marked by a choking incident, mealtime stress, or forced feeding. “Challenges differ between a difficult 3-year-old and a 6- or 7-year-old who still refuses new foods,” he explained.
Parental Pressure and Nutritional Balance
Nutritional balance is essential, but “parental pressure is often too high.” Parents worry because they see food as a “nutraceutical.” Bellaïche recommended defusing anxiety by keeping mealtimes calm, allowing the child to eat at their pace, avoiding force-feeding, keeping meals brief, and avoiding snacks. While “it’s important to stay vigilant — as it’s incorrect to assume a child won’t let themselves starve — most cases can be managed in general practice through parental guidance, empathy, and a positive approach.”
Monitoring growth and weight curves is crucial, with the Kanawati index (ratio of arm circumference to head circumference) being a reliable indicator for specialist referral if < 0.31. A varied diet is important for nutritional balance; when this isn’t achieved, continued consumption of toddler formula after age 3 can prevent iron and calcium deficiencies.
When eating difficulties are documented, healthcare providers should investigate for underlying organic, digestive, or extra-digestive diseases (neurologic, cardiac, renal, etc.). “It’s best not to hastily diagnose cow’s milk protein allergy,” Bellaïche advised, as cases are relatively rare and unnecessarily eliminating milk can complicate a child’s relationship with food. Similarly, gastroesophageal reflux disease should be objectively diagnosed to avoid unnecessary proton pump inhibitor treatment and associated side effects.
For children with low birth weight, mild congenital heart disease, or suggestive dysmorphology, consider evaluating for a genetic syndrome.
Avoidant/Restrictive Food Intake Disorder (ARFID)
ARFID is marked by a lack of interest in food and avoidance due to sensory characteristics. Often observed in anxious children, ARFID is diagnosed in approximately 20% of children with autism spectrum disorder, where food selectivity is prevalent. This condition can hinder a child’s development and may necessitate nutritional supplementation.
Case Profiles in Eating Issues
Bellaïche outlined three typical cases among children considered “picky eaters”:
- The small eater: Often near the lower growth curve limits, this child “grazes and doesn’t sit still.” These children are usually active and have a family history of similar eating habits. Parents should encourage psychomotor activities, discourage snacks outside of mealtimes, and consider fun family picnics on the floor, offering a mezze-style variety of foods.
- The child with a history of trauma: Children with trauma (from intubation, nasogastric tubes, severe vomiting, forced feeding, or choking) may develop aversions requiring behavioral intervention.
- The child with high sensory sensitivity: This child dislikes getting the hands dirty, avoids mouthing objects, or resists certain textures, such as grass and sand. Gradual behavioral approaches with sensory play and visually appealing new foods can be beneficial. Guided self-led food exploration (baby-led weaning) may also help, though dairy intake is often needed to prevent deficiencies during this stage.
Finally, gastroesophageal reflux disease or constipation can contribute to appetite loss. Studies have shown that treating these issues can improve appetite in small eaters.
This story was translated from Univadis France using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
FROM JNMG 2024
IBS: Understanding a Common Yet Misunderstood Condition
Irritable bowel syndrome (IBS) is one of the most common conditions encountered by both primary care providers and gastroenterologists, with a pooled global prevalence of 11.2%. This functional bowel disorder is characterized by abdominal pain or discomfort, diarrhea and/or constipation, and bloating.
Unfortunately, , according to Alan Desmond, MB, consultant in gastroenterology and general internal medicine, Torbay Hospital, UK National Health Service.
Desmond regularly sees patients who either haven’t been accurately diagnosed or have been told, “Don’t worry, it’s ‘just’ irritable bowel syndrome,” he said at the recent International Conference on Nutrition in Medicine.
A 2017 study involving nearly 2000 patients with a history of gastrointestinal (GI) symptoms found that 43.1% of those who met the criteria for IBS were undiagnosed, and among those who were diagnosed, 26% were not receiving treatment.
“Many clinicians vastly underestimate the impact functional GI symptoms have on our patients in lack of productivity, becoming homebound or losing employment, the inability to enjoy a meal with friends or family, and always needing to know where the nearest bathroom is, for example,” Desmond said in an interview.
IBS can profoundly affect patients’ mental health. One study found that 38% of patients with IBS attending a tertiary care clinic contemplated suicide because they felt hopeless about ever achieving symptom relief.
Today, several dietary, pharmacologic, and psychological/behavioral approaches are available to treat patients with IBS, noted William D. Chey, MD, AGAF, chief of the Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, Michigan.
“Each individual patient may need a different combination of these foundational treatments,” he said. “One size doesn’t fit all.”
Diagnostic Pathway
One reason IBS is so hard to diagnose is that it’s a “symptom-based disorder, with identification of the condition predicated upon certain key characteristics that are heterogeneous,” Chey said in an interview. “IBS in patient ‘A’ may not present the same way as IBS in patient ‘B,’ although there are certain foundational common characteristics.”
IBS involves “abnormalities in the motility and contractility of the GI tract,” he said. It can present with diarrhea (IBS-D), constipation (IBS-C), or a mixture or alternation of diarrhea and constipation (IBS-M).
Patients with IBS-D often have an exaggerated gastro-colonic response, while those with IBS-C often have a blunted response.
Beyond stool abnormalities and abdominal pain/discomfort, patients often report bloating/distension, low backache, lethargy, nausea, thigh pain, and urinary and gynecologic symptoms.
Historically, IBS has been regarded as a “diagnosis of exclusion” because classic diagnostic tests typically yield no concrete findings. Desmond noted that several blood tests, procedures, imaging studies, and other tests are available to rule out other organic GI conditions, as outlined in the Table.
If the patient comes from a geographical region where giardia is endemic, clinicians also should consider testing for the parasite, Chey said.
New Understanding of IBS Etiology
Now, advances in the understanding of IBS are changing the approach to the disease.
“The field is moving away from seeing IBS as a ‘wastebasket diagnosis,’ recognizing that there are other causes of a patient’s symptoms,” Mark Pimentel, MD, associate professor of medicine and gastroenterology, Cedars-Sinai, Los Angeles, said in an interview. “What’s made IBS so difficult to diagnose has been the absence of biological markers and hallmark findings on endoscopy.”
Recent research points to novel bacterial causes as culprits in the development of IBS. In particular, altered small bowel microbiota can be triggered by acute gastroenteritis.
Food poisoning can trigger the onset of IBS — a phenomenon called “postinfectious IBS (PI-IBS),” said Pimentel, who is also executive director of the Medically Associated Science and Technology Program at Cedars-Sinai. PI-IBS almost always takes the form of IBS-D, with up to 60% of patients with IBS-D suffering the long-term sequelae of food poisoning.
The types of bacteria most commonly associated with gastroenteritis are Shigella, Campylobacter, Salmonella, and Escherichia coli, Pimentel said. All of them release cytolethal distending toxin B (CdtB), causing the body to produce antibodies to the toxin.
CdtB resembles vinculin, a naturally occurring protein critical for healthy gut function. “Because of this molecular resemblance, the immune system often mistakes one for the other, producing anti-vinculin,” Pimentel explained.
This autoimmune response leads to disruptions in the gut microbiome, ultimately resulting in PI-IBS. The chain of events “doesn’t necessarily happen immediately,” Pimentel said. “You might have developed food poisoning at a party weeks or months ago.”
Acute gastroenteritis is common, affecting as many as 179 million people in the United States annually. A meta-analysis of 47 studies, incorporating 28,270 patients, found that those who had experienced acute gastroenteritis had a fourfold higher risk of developing IBS compared with nonexposed controls.
“The problem isn’t only the IBS itself, but the fact that people with PI-IBS are four times as likely to contract food poisoning again, which can further exacerbate IBS symptoms,” Pimentel said.
Diarrhea-predominant IBS can be detected through the presence of two blood biomarkers — anti-CdtB and anti-vinculin — in a blood test developed by Pimentel and his group.
“Elevation in either of these biomarkers establishes the diagnosis,” Pimentel said. “This is a breakthrough because it represents the first test that can make IBS a ‘diagnosis of inclusion.’”
The blood test also can identify IBS-M but not IBS-C.
Pimentel said that IBS-C is associated with increased levels of methanogenic archaea, which can be diagnosed by a positive methane breath test. “Methane gas slows intestinal contractility, which might result in constipation,” he said.
Diet as a Treatment Option
Diet is usually the starting point for IBS treatment, Chey said. “The standard dietary recommendations, as defined by the National Institute for Health and Care Excellence Guidance for managing IBS, are reasonable and common sense — eating three meals a day, avoiding carbonated beverages, excess alcohol, and excess caffeine, and avoiding hard-to-digest foods that can be gas producing.”
A diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), which are carbohydrates that aren’t completely absorbed in the intestines, has been shown to be effective in alleviating GI distress in as many as 86% of patients with IBS, leading to improvements in overall GI symptoms as well as individual symptoms (eg, abdominal pain, bloating, constipation, diarrhea, and flatulence).
Desmond recommends the low FODMAP program delineated by Monash University in Australia. The diet should be undertaken only under the supervision of a dietitian, he warned. Moreover, following it on a long-term basis can have an adverse impact on dietary quality and the gut microbiome. Therefore, “it’s important to embark on stepwise reintroduction of FODMAPS under supervision to find acceptable thresholds that don’t cause a return of symptoms.”
A growing body of research suggests that following the Mediterranean diet can be helpful in reducing IBS symptoms. Chey said that some patients who tend to over-restrict their eating might benefit from a less restrictive diet than the typical low FODMAPs diet. For them, the Mediterranean diet may be a good option.
Pharmacotherapy for IBS
Nutritional approaches aren’t for everyone, Chey noted. “Some people don’t want to be on a highly restricted diet.” For them, medications addressing symptoms might be a better option.
Antispasmodics — either anticholinergics (hyoscine and dicyclomine) or smooth muscle relaxants (alverine, mebeverine, and peppermint oil) — can be helpful, although they can worsen constipation in a dose-dependent manner. It is advisable to use them on an as-needed rather than long-term basis.
Antidiarrheal agents include loperamide and diphenoxylate.
For constipation, laxatives (eg, senna, bisacodyl, polyethylene glycol, and sodium picosulfate) can be helpful.
Desmond noted that the American Gastroenterological Association does not recommend routine use of probiotics for most GI disorders, including IBS. Exceptions include prevention of Clostridioides difficile, ulcerative colitis, and pouchitis.
Targeting the Gut-Brain Relationship
Stress plays a role in exacerbating symptoms in patients with IBS and is an important target for intervention.
“If patients are living with a level of stress that’s impairing, we won’t be able to solve their gut issues until we resolve their stress issues,” Desmond said. “We need to calm the gut-microbiome-brain axis, which is multidimensional and bidirectional.”
Many people — even those without IBS — experience queasiness or diarrhea prior to a major event they’re nervous about, Chey noted. These events activate the brain, which activates the nervous system, which interacts with the GI tract. Indeed, IBS is now recognized as a disorder of gut-brain interaction, he said.
“We now know that the microbiome in the GI tract influences cognition and emotional function, depression, and anxiety. One might say that the gut is the ‘center of the universe’ to human beings,” Chey said.
Evidence-based psychological approaches for stress reduction in patients with IBS include cognitive behavioral therapy, specifically tailored to helping the patient identify associations between IBS symptoms and thoughts, emotions, and actions, as well as learning new behaviors and engaging in stress management. Psychodynamic (interpersonal) therapy enables patients to understand the connection between GI symptoms and interpersonal conflicts, emotional factors, or relationship difficulties.
Gut-directed hypnotherapy (GDH) is a “proven modality for IBS,” Desmond said. Unlike other forms of hypnotherapy, GDH focuses specifically on controlling and normalizing GI function. Studies have shown a reduction of ≥ 30% in abdominal pain in two thirds of participants, with overall response rates up to 85%. It can be delivered in an individual or group setting or via a smartphone.
Desmond recommends mindfulness-based therapy (MBT) for IBS. MBT focuses on the “cultivation of mindfulness, defined as intentional, nonjudgmental, present-focused awareness.” It has been found effective in reducing flares and the markers of gut inflammation in ulcerative colitis, as well as reducing symptoms of IBS.
Chey noted that an emerging body of literature supports the potential role of acupuncture in treating IBS, and his clinic employs it. “I would like to see further research into other areas of CAM [complementary and alternative medicine], including herbal approaches to IBS symptoms as well as stress.”
Finally, all the experts agree that more research is needed.
“The real tragedy is that the NIH invests next to nothing in IBS, in contrast to inflammatory bowel disease and many other conditions,” Pimentel said. “Yet IBS is 45 times more common than inflammatory bowel disease.”
Pimentel hopes that with enough advocacy and recognition that IBS isn’t “just stress-related,” more resources will be devoted to understanding this debilitating condition.
Desmond is the author of a book on the benefits of a plant-based diet. He has also received honoraria, speaking, and consultancy fees from the European Space Agency, Dyson Institute of Engineering and Technology, Riverford Organic Farmers, Ltd., Salesforce Inc., Sentara Healthcare, Saudi Sports for All Federation, the Physicians Committee for Responsible Medicine, The Plantrician Project, Doctors for Nutrition, and The Happy Pear.
Pimentel is a consultant for Bausch Health, Ferring Pharmaceuticals, and Ardelyx. He holds equity in and is also a consultant for Dieta Health, Salvo Health, Cylinder Health, and Gemelli Biotech. Cedars-Sinai has a licensing agreement with Gemelli Biotech and Hobbs Medical.
Chey is a consultant to AbbVie, Ardelyx, Atmo, Biomerica, Gemelli Biotech, Ironwood Pharmaceuticals, Nestlé, QOL Medical, Phathom Pharmaceuticals, Redhill, Salix/Valeant, Takeda, and Vibrant. He receives grant/research funding from Commonwealth Diagnostics International, Inc., US Food and Drug Administration, National Institutes of Health, QOL Medical, and Salix/Valeant. He holds stock options in Coprata, Dieta Health, Evinature, FoodMarble, Kiwi Biosciences, and ModifyHealth. He is a board or advisory panel member of the American College of Gastroenterology, GI Health Foundation, International Foundation for Gastrointestinal Disorders, Rome. He holds patents on My Nutrition Health, Digital Manometry, and Rectal Expulsion Device.
A version of this article appeared on Medscape.com.
Irritable bowel syndrome (IBS) is one of the most common conditions encountered by both primary care providers and gastroenterologists, with a pooled global prevalence of 11.2%. This functional bowel disorder is characterized by abdominal pain or discomfort, diarrhea and/or constipation, and bloating.
Unfortunately, , according to Alan Desmond, MB, consultant in gastroenterology and general internal medicine, Torbay Hospital, UK National Health Service.
Desmond regularly sees patients who either haven’t been accurately diagnosed or have been told, “Don’t worry, it’s ‘just’ irritable bowel syndrome,” he said at the recent International Conference on Nutrition in Medicine.
A 2017 study involving nearly 2000 patients with a history of gastrointestinal (GI) symptoms found that 43.1% of those who met the criteria for IBS were undiagnosed, and among those who were diagnosed, 26% were not receiving treatment.
“Many clinicians vastly underestimate the impact functional GI symptoms have on our patients in lack of productivity, becoming homebound or losing employment, the inability to enjoy a meal with friends or family, and always needing to know where the nearest bathroom is, for example,” Desmond said in an interview.
IBS can profoundly affect patients’ mental health. One study found that 38% of patients with IBS attending a tertiary care clinic contemplated suicide because they felt hopeless about ever achieving symptom relief.
Today, several dietary, pharmacologic, and psychological/behavioral approaches are available to treat patients with IBS, noted William D. Chey, MD, AGAF, chief of the Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, Michigan.
“Each individual patient may need a different combination of these foundational treatments,” he said. “One size doesn’t fit all.”
Diagnostic Pathway
One reason IBS is so hard to diagnose is that it’s a “symptom-based disorder, with identification of the condition predicated upon certain key characteristics that are heterogeneous,” Chey said in an interview. “IBS in patient ‘A’ may not present the same way as IBS in patient ‘B,’ although there are certain foundational common characteristics.”
IBS involves “abnormalities in the motility and contractility of the GI tract,” he said. It can present with diarrhea (IBS-D), constipation (IBS-C), or a mixture or alternation of diarrhea and constipation (IBS-M).
Patients with IBS-D often have an exaggerated gastro-colonic response, while those with IBS-C often have a blunted response.
Beyond stool abnormalities and abdominal pain/discomfort, patients often report bloating/distension, low backache, lethargy, nausea, thigh pain, and urinary and gynecologic symptoms.
Historically, IBS has been regarded as a “diagnosis of exclusion” because classic diagnostic tests typically yield no concrete findings. Desmond noted that several blood tests, procedures, imaging studies, and other tests are available to rule out other organic GI conditions, as outlined in the Table.
If the patient comes from a geographical region where giardia is endemic, clinicians also should consider testing for the parasite, Chey said.
New Understanding of IBS Etiology
Now, advances in the understanding of IBS are changing the approach to the disease.
“The field is moving away from seeing IBS as a ‘wastebasket diagnosis,’ recognizing that there are other causes of a patient’s symptoms,” Mark Pimentel, MD, associate professor of medicine and gastroenterology, Cedars-Sinai, Los Angeles, said in an interview. “What’s made IBS so difficult to diagnose has been the absence of biological markers and hallmark findings on endoscopy.”
Recent research points to novel bacterial causes as culprits in the development of IBS. In particular, altered small bowel microbiota can be triggered by acute gastroenteritis.
Food poisoning can trigger the onset of IBS — a phenomenon called “postinfectious IBS (PI-IBS),” said Pimentel, who is also executive director of the Medically Associated Science and Technology Program at Cedars-Sinai. PI-IBS almost always takes the form of IBS-D, with up to 60% of patients with IBS-D suffering the long-term sequelae of food poisoning.
The types of bacteria most commonly associated with gastroenteritis are Shigella, Campylobacter, Salmonella, and Escherichia coli, Pimentel said. All of them release cytolethal distending toxin B (CdtB), causing the body to produce antibodies to the toxin.
CdtB resembles vinculin, a naturally occurring protein critical for healthy gut function. “Because of this molecular resemblance, the immune system often mistakes one for the other, producing anti-vinculin,” Pimentel explained.
This autoimmune response leads to disruptions in the gut microbiome, ultimately resulting in PI-IBS. The chain of events “doesn’t necessarily happen immediately,” Pimentel said. “You might have developed food poisoning at a party weeks or months ago.”
Acute gastroenteritis is common, affecting as many as 179 million people in the United States annually. A meta-analysis of 47 studies, incorporating 28,270 patients, found that those who had experienced acute gastroenteritis had a fourfold higher risk of developing IBS compared with nonexposed controls.
“The problem isn’t only the IBS itself, but the fact that people with PI-IBS are four times as likely to contract food poisoning again, which can further exacerbate IBS symptoms,” Pimentel said.
Diarrhea-predominant IBS can be detected through the presence of two blood biomarkers — anti-CdtB and anti-vinculin — in a blood test developed by Pimentel and his group.
“Elevation in either of these biomarkers establishes the diagnosis,” Pimentel said. “This is a breakthrough because it represents the first test that can make IBS a ‘diagnosis of inclusion.’”
The blood test also can identify IBS-M but not IBS-C.
Pimentel said that IBS-C is associated with increased levels of methanogenic archaea, which can be diagnosed by a positive methane breath test. “Methane gas slows intestinal contractility, which might result in constipation,” he said.
Diet as a Treatment Option
Diet is usually the starting point for IBS treatment, Chey said. “The standard dietary recommendations, as defined by the National Institute for Health and Care Excellence Guidance for managing IBS, are reasonable and common sense — eating three meals a day, avoiding carbonated beverages, excess alcohol, and excess caffeine, and avoiding hard-to-digest foods that can be gas producing.”
A diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), which are carbohydrates that aren’t completely absorbed in the intestines, has been shown to be effective in alleviating GI distress in as many as 86% of patients with IBS, leading to improvements in overall GI symptoms as well as individual symptoms (eg, abdominal pain, bloating, constipation, diarrhea, and flatulence).
Desmond recommends the low FODMAP program delineated by Monash University in Australia. The diet should be undertaken only under the supervision of a dietitian, he warned. Moreover, following it on a long-term basis can have an adverse impact on dietary quality and the gut microbiome. Therefore, “it’s important to embark on stepwise reintroduction of FODMAPS under supervision to find acceptable thresholds that don’t cause a return of symptoms.”
A growing body of research suggests that following the Mediterranean diet can be helpful in reducing IBS symptoms. Chey said that some patients who tend to over-restrict their eating might benefit from a less restrictive diet than the typical low FODMAPs diet. For them, the Mediterranean diet may be a good option.
Pharmacotherapy for IBS
Nutritional approaches aren’t for everyone, Chey noted. “Some people don’t want to be on a highly restricted diet.” For them, medications addressing symptoms might be a better option.
Antispasmodics — either anticholinergics (hyoscine and dicyclomine) or smooth muscle relaxants (alverine, mebeverine, and peppermint oil) — can be helpful, although they can worsen constipation in a dose-dependent manner. It is advisable to use them on an as-needed rather than long-term basis.
Antidiarrheal agents include loperamide and diphenoxylate.
For constipation, laxatives (eg, senna, bisacodyl, polyethylene glycol, and sodium picosulfate) can be helpful.
Desmond noted that the American Gastroenterological Association does not recommend routine use of probiotics for most GI disorders, including IBS. Exceptions include prevention of Clostridioides difficile, ulcerative colitis, and pouchitis.
Targeting the Gut-Brain Relationship
Stress plays a role in exacerbating symptoms in patients with IBS and is an important target for intervention.
“If patients are living with a level of stress that’s impairing, we won’t be able to solve their gut issues until we resolve their stress issues,” Desmond said. “We need to calm the gut-microbiome-brain axis, which is multidimensional and bidirectional.”
Many people — even those without IBS — experience queasiness or diarrhea prior to a major event they’re nervous about, Chey noted. These events activate the brain, which activates the nervous system, which interacts with the GI tract. Indeed, IBS is now recognized as a disorder of gut-brain interaction, he said.
“We now know that the microbiome in the GI tract influences cognition and emotional function, depression, and anxiety. One might say that the gut is the ‘center of the universe’ to human beings,” Chey said.
Evidence-based psychological approaches for stress reduction in patients with IBS include cognitive behavioral therapy, specifically tailored to helping the patient identify associations between IBS symptoms and thoughts, emotions, and actions, as well as learning new behaviors and engaging in stress management. Psychodynamic (interpersonal) therapy enables patients to understand the connection between GI symptoms and interpersonal conflicts, emotional factors, or relationship difficulties.
Gut-directed hypnotherapy (GDH) is a “proven modality for IBS,” Desmond said. Unlike other forms of hypnotherapy, GDH focuses specifically on controlling and normalizing GI function. Studies have shown a reduction of ≥ 30% in abdominal pain in two thirds of participants, with overall response rates up to 85%. It can be delivered in an individual or group setting or via a smartphone.
Desmond recommends mindfulness-based therapy (MBT) for IBS. MBT focuses on the “cultivation of mindfulness, defined as intentional, nonjudgmental, present-focused awareness.” It has been found effective in reducing flares and the markers of gut inflammation in ulcerative colitis, as well as reducing symptoms of IBS.
Chey noted that an emerging body of literature supports the potential role of acupuncture in treating IBS, and his clinic employs it. “I would like to see further research into other areas of CAM [complementary and alternative medicine], including herbal approaches to IBS symptoms as well as stress.”
Finally, all the experts agree that more research is needed.
“The real tragedy is that the NIH invests next to nothing in IBS, in contrast to inflammatory bowel disease and many other conditions,” Pimentel said. “Yet IBS is 45 times more common than inflammatory bowel disease.”
Pimentel hopes that with enough advocacy and recognition that IBS isn’t “just stress-related,” more resources will be devoted to understanding this debilitating condition.
Desmond is the author of a book on the benefits of a plant-based diet. He has also received honoraria, speaking, and consultancy fees from the European Space Agency, Dyson Institute of Engineering and Technology, Riverford Organic Farmers, Ltd., Salesforce Inc., Sentara Healthcare, Saudi Sports for All Federation, the Physicians Committee for Responsible Medicine, The Plantrician Project, Doctors for Nutrition, and The Happy Pear.
Pimentel is a consultant for Bausch Health, Ferring Pharmaceuticals, and Ardelyx. He holds equity in and is also a consultant for Dieta Health, Salvo Health, Cylinder Health, and Gemelli Biotech. Cedars-Sinai has a licensing agreement with Gemelli Biotech and Hobbs Medical.
Chey is a consultant to AbbVie, Ardelyx, Atmo, Biomerica, Gemelli Biotech, Ironwood Pharmaceuticals, Nestlé, QOL Medical, Phathom Pharmaceuticals, Redhill, Salix/Valeant, Takeda, and Vibrant. He receives grant/research funding from Commonwealth Diagnostics International, Inc., US Food and Drug Administration, National Institutes of Health, QOL Medical, and Salix/Valeant. He holds stock options in Coprata, Dieta Health, Evinature, FoodMarble, Kiwi Biosciences, and ModifyHealth. He is a board or advisory panel member of the American College of Gastroenterology, GI Health Foundation, International Foundation for Gastrointestinal Disorders, Rome. He holds patents on My Nutrition Health, Digital Manometry, and Rectal Expulsion Device.
A version of this article appeared on Medscape.com.
Irritable bowel syndrome (IBS) is one of the most common conditions encountered by both primary care providers and gastroenterologists, with a pooled global prevalence of 11.2%. This functional bowel disorder is characterized by abdominal pain or discomfort, diarrhea and/or constipation, and bloating.
Unfortunately, , according to Alan Desmond, MB, consultant in gastroenterology and general internal medicine, Torbay Hospital, UK National Health Service.
Desmond regularly sees patients who either haven’t been accurately diagnosed or have been told, “Don’t worry, it’s ‘just’ irritable bowel syndrome,” he said at the recent International Conference on Nutrition in Medicine.
A 2017 study involving nearly 2000 patients with a history of gastrointestinal (GI) symptoms found that 43.1% of those who met the criteria for IBS were undiagnosed, and among those who were diagnosed, 26% were not receiving treatment.
“Many clinicians vastly underestimate the impact functional GI symptoms have on our patients in lack of productivity, becoming homebound or losing employment, the inability to enjoy a meal with friends or family, and always needing to know where the nearest bathroom is, for example,” Desmond said in an interview.
IBS can profoundly affect patients’ mental health. One study found that 38% of patients with IBS attending a tertiary care clinic contemplated suicide because they felt hopeless about ever achieving symptom relief.
Today, several dietary, pharmacologic, and psychological/behavioral approaches are available to treat patients with IBS, noted William D. Chey, MD, AGAF, chief of the Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, Michigan.
“Each individual patient may need a different combination of these foundational treatments,” he said. “One size doesn’t fit all.”
Diagnostic Pathway
One reason IBS is so hard to diagnose is that it’s a “symptom-based disorder, with identification of the condition predicated upon certain key characteristics that are heterogeneous,” Chey said in an interview. “IBS in patient ‘A’ may not present the same way as IBS in patient ‘B,’ although there are certain foundational common characteristics.”
IBS involves “abnormalities in the motility and contractility of the GI tract,” he said. It can present with diarrhea (IBS-D), constipation (IBS-C), or a mixture or alternation of diarrhea and constipation (IBS-M).
Patients with IBS-D often have an exaggerated gastro-colonic response, while those with IBS-C often have a blunted response.
Beyond stool abnormalities and abdominal pain/discomfort, patients often report bloating/distension, low backache, lethargy, nausea, thigh pain, and urinary and gynecologic symptoms.
Historically, IBS has been regarded as a “diagnosis of exclusion” because classic diagnostic tests typically yield no concrete findings. Desmond noted that several blood tests, procedures, imaging studies, and other tests are available to rule out other organic GI conditions, as outlined in the Table.
If the patient comes from a geographical region where giardia is endemic, clinicians also should consider testing for the parasite, Chey said.
New Understanding of IBS Etiology
Now, advances in the understanding of IBS are changing the approach to the disease.
“The field is moving away from seeing IBS as a ‘wastebasket diagnosis,’ recognizing that there are other causes of a patient’s symptoms,” Mark Pimentel, MD, associate professor of medicine and gastroenterology, Cedars-Sinai, Los Angeles, said in an interview. “What’s made IBS so difficult to diagnose has been the absence of biological markers and hallmark findings on endoscopy.”
Recent research points to novel bacterial causes as culprits in the development of IBS. In particular, altered small bowel microbiota can be triggered by acute gastroenteritis.
Food poisoning can trigger the onset of IBS — a phenomenon called “postinfectious IBS (PI-IBS),” said Pimentel, who is also executive director of the Medically Associated Science and Technology Program at Cedars-Sinai. PI-IBS almost always takes the form of IBS-D, with up to 60% of patients with IBS-D suffering the long-term sequelae of food poisoning.
The types of bacteria most commonly associated with gastroenteritis are Shigella, Campylobacter, Salmonella, and Escherichia coli, Pimentel said. All of them release cytolethal distending toxin B (CdtB), causing the body to produce antibodies to the toxin.
CdtB resembles vinculin, a naturally occurring protein critical for healthy gut function. “Because of this molecular resemblance, the immune system often mistakes one for the other, producing anti-vinculin,” Pimentel explained.
This autoimmune response leads to disruptions in the gut microbiome, ultimately resulting in PI-IBS. The chain of events “doesn’t necessarily happen immediately,” Pimentel said. “You might have developed food poisoning at a party weeks or months ago.”
Acute gastroenteritis is common, affecting as many as 179 million people in the United States annually. A meta-analysis of 47 studies, incorporating 28,270 patients, found that those who had experienced acute gastroenteritis had a fourfold higher risk of developing IBS compared with nonexposed controls.
“The problem isn’t only the IBS itself, but the fact that people with PI-IBS are four times as likely to contract food poisoning again, which can further exacerbate IBS symptoms,” Pimentel said.
Diarrhea-predominant IBS can be detected through the presence of two blood biomarkers — anti-CdtB and anti-vinculin — in a blood test developed by Pimentel and his group.
“Elevation in either of these biomarkers establishes the diagnosis,” Pimentel said. “This is a breakthrough because it represents the first test that can make IBS a ‘diagnosis of inclusion.’”
The blood test also can identify IBS-M but not IBS-C.
Pimentel said that IBS-C is associated with increased levels of methanogenic archaea, which can be diagnosed by a positive methane breath test. “Methane gas slows intestinal contractility, which might result in constipation,” he said.
Diet as a Treatment Option
Diet is usually the starting point for IBS treatment, Chey said. “The standard dietary recommendations, as defined by the National Institute for Health and Care Excellence Guidance for managing IBS, are reasonable and common sense — eating three meals a day, avoiding carbonated beverages, excess alcohol, and excess caffeine, and avoiding hard-to-digest foods that can be gas producing.”
A diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), which are carbohydrates that aren’t completely absorbed in the intestines, has been shown to be effective in alleviating GI distress in as many as 86% of patients with IBS, leading to improvements in overall GI symptoms as well as individual symptoms (eg, abdominal pain, bloating, constipation, diarrhea, and flatulence).
Desmond recommends the low FODMAP program delineated by Monash University in Australia. The diet should be undertaken only under the supervision of a dietitian, he warned. Moreover, following it on a long-term basis can have an adverse impact on dietary quality and the gut microbiome. Therefore, “it’s important to embark on stepwise reintroduction of FODMAPS under supervision to find acceptable thresholds that don’t cause a return of symptoms.”
A growing body of research suggests that following the Mediterranean diet can be helpful in reducing IBS symptoms. Chey said that some patients who tend to over-restrict their eating might benefit from a less restrictive diet than the typical low FODMAPs diet. For them, the Mediterranean diet may be a good option.
Pharmacotherapy for IBS
Nutritional approaches aren’t for everyone, Chey noted. “Some people don’t want to be on a highly restricted diet.” For them, medications addressing symptoms might be a better option.
Antispasmodics — either anticholinergics (hyoscine and dicyclomine) or smooth muscle relaxants (alverine, mebeverine, and peppermint oil) — can be helpful, although they can worsen constipation in a dose-dependent manner. It is advisable to use them on an as-needed rather than long-term basis.
Antidiarrheal agents include loperamide and diphenoxylate.
For constipation, laxatives (eg, senna, bisacodyl, polyethylene glycol, and sodium picosulfate) can be helpful.
Desmond noted that the American Gastroenterological Association does not recommend routine use of probiotics for most GI disorders, including IBS. Exceptions include prevention of Clostridioides difficile, ulcerative colitis, and pouchitis.
Targeting the Gut-Brain Relationship
Stress plays a role in exacerbating symptoms in patients with IBS and is an important target for intervention.
“If patients are living with a level of stress that’s impairing, we won’t be able to solve their gut issues until we resolve their stress issues,” Desmond said. “We need to calm the gut-microbiome-brain axis, which is multidimensional and bidirectional.”
Many people — even those without IBS — experience queasiness or diarrhea prior to a major event they’re nervous about, Chey noted. These events activate the brain, which activates the nervous system, which interacts with the GI tract. Indeed, IBS is now recognized as a disorder of gut-brain interaction, he said.
“We now know that the microbiome in the GI tract influences cognition and emotional function, depression, and anxiety. One might say that the gut is the ‘center of the universe’ to human beings,” Chey said.
Evidence-based psychological approaches for stress reduction in patients with IBS include cognitive behavioral therapy, specifically tailored to helping the patient identify associations between IBS symptoms and thoughts, emotions, and actions, as well as learning new behaviors and engaging in stress management. Psychodynamic (interpersonal) therapy enables patients to understand the connection between GI symptoms and interpersonal conflicts, emotional factors, or relationship difficulties.
Gut-directed hypnotherapy (GDH) is a “proven modality for IBS,” Desmond said. Unlike other forms of hypnotherapy, GDH focuses specifically on controlling and normalizing GI function. Studies have shown a reduction of ≥ 30% in abdominal pain in two thirds of participants, with overall response rates up to 85%. It can be delivered in an individual or group setting or via a smartphone.
Desmond recommends mindfulness-based therapy (MBT) for IBS. MBT focuses on the “cultivation of mindfulness, defined as intentional, nonjudgmental, present-focused awareness.” It has been found effective in reducing flares and the markers of gut inflammation in ulcerative colitis, as well as reducing symptoms of IBS.
Chey noted that an emerging body of literature supports the potential role of acupuncture in treating IBS, and his clinic employs it. “I would like to see further research into other areas of CAM [complementary and alternative medicine], including herbal approaches to IBS symptoms as well as stress.”
Finally, all the experts agree that more research is needed.
“The real tragedy is that the NIH invests next to nothing in IBS, in contrast to inflammatory bowel disease and many other conditions,” Pimentel said. “Yet IBS is 45 times more common than inflammatory bowel disease.”
Pimentel hopes that with enough advocacy and recognition that IBS isn’t “just stress-related,” more resources will be devoted to understanding this debilitating condition.
Desmond is the author of a book on the benefits of a plant-based diet. He has also received honoraria, speaking, and consultancy fees from the European Space Agency, Dyson Institute of Engineering and Technology, Riverford Organic Farmers, Ltd., Salesforce Inc., Sentara Healthcare, Saudi Sports for All Federation, the Physicians Committee for Responsible Medicine, The Plantrician Project, Doctors for Nutrition, and The Happy Pear.
Pimentel is a consultant for Bausch Health, Ferring Pharmaceuticals, and Ardelyx. He holds equity in and is also a consultant for Dieta Health, Salvo Health, Cylinder Health, and Gemelli Biotech. Cedars-Sinai has a licensing agreement with Gemelli Biotech and Hobbs Medical.
Chey is a consultant to AbbVie, Ardelyx, Atmo, Biomerica, Gemelli Biotech, Ironwood Pharmaceuticals, Nestlé, QOL Medical, Phathom Pharmaceuticals, Redhill, Salix/Valeant, Takeda, and Vibrant. He receives grant/research funding from Commonwealth Diagnostics International, Inc., US Food and Drug Administration, National Institutes of Health, QOL Medical, and Salix/Valeant. He holds stock options in Coprata, Dieta Health, Evinature, FoodMarble, Kiwi Biosciences, and ModifyHealth. He is a board or advisory panel member of the American College of Gastroenterology, GI Health Foundation, International Foundation for Gastrointestinal Disorders, Rome. He holds patents on My Nutrition Health, Digital Manometry, and Rectal Expulsion Device.
A version of this article appeared on Medscape.com.
Breath Gas Patterns Predict Response to Low FODMAP Diet
PHILADELPHIA — , according to a new study.
The low FODMAP diet is the most evidence-based dietary therapy for patients with IBS, but we know that “only about 50% of our patients respond to it,” said principal investigator Prashant Singh, MD, assistant professor at the University of Michigan in Ann Arbor, Michigan. “Exhaled breath gases represent bacterial fermentation of dietary carbohydrates. These measurements could provide a simple biomarker for response to low FODMAP diets.”
Even before starting the low FODMAP diet, “you could see notable differences in breath test patterns between responders and nonresponders,” he said. “We saw that low FODMAP responders had higher hydrogen (H2) and lower methane (CH4) at baseline than nonresponders and had a greater drop in hydrogen following FODMAP restriction vs nonresponders.”
He added that these results imply that responders to this diet may exhibit differences in baseline microbiota composition regarding saccharolytic capacity and/or methanogens.
Singh presented the findings at the American College of Gastroenterology (ACG) 2024 Annual Scientific Meeting.
Breaths That Can Predict Response
To determine if pre-intervention non-fasting breath patterns are associated with a clinical response to low FODMAP diets, Singh and colleagues enrolled 284 self-selected participants (mean age, 45.2 years) with mild to moderate gastrointestinal (GI) symptoms. Participants used an app-connected breath analyzer to record hourly, non-fasting H2 and CH4 levels during waking hours, in addition to logging meal content and symptom severity (bloating, abdominal pain, and flatulence) on a 0-10 scale.
Patients were directed to consume their habitual diet for 1 week, before following an app-directed low FODMAP diet for 1 week. Responders were defined as those with a ≥ 30% reduction in at least one mean symptom score. The researchers then compared average hourly H2 and CH4 levels and symptom scores at baseline between low FODMAP diet responders and nonresponders.
Of the participants, 111 were classified as responders and 173 as nonresponders. There were no significant differences between the groups in gender, age, body mass index, or FODMAP per calorie.
Following FODMAP restriction, responders had consistently lower abdominal pain throughout the day and lower bloating and flatulence predominantly in the latter part of the day. Nonresponders experienced no significant changes in key abdominal symptoms after adopting the low FODMAP diet.
The researchers found that breath tests taken at baseline revealed predictive trends between the groups, even though average FODMAP consumption did not significantly differ between them. Baseline H2 levels were higher among responders than among nonresponders, especially in the morning and evening. However, responders had lower baseline CH4 levels throughout the day.
Following FODMAP restrictions, responders had a significant drop in non-fasting H2 but not CH4, whereas nonresponders did not have a significant drop in either.
The study was limited by the fact that participants were not clinically diagnosed with IBS, their GI symptoms were mild overall, and no data were available on stool consistency/frequency or fecal microbiome composition for correlation with exhaled breath gas levels.
A Potential New Biomarker
Session co-moderator Kyle Staller, MD, MPH, director of the Gastrointestinal Motility Laboratory at Mass General and associate professor of medicine at Harvard Medical School in Boston, Massachusetts, said in an interview that if validated, these findings provide hope for better directing low FODMAP diets to those patients who may benefit.
There are some patients who may or may not respond to a FODMAP diet, for reasons we don’t yet know, possibly related to fermentation of gas, and it’s helpful to know before starting treatment, he said. It may help us with more of “a precision medicine approach before we really torture people with diets that can be very difficult to adhere to.”
Staller, who was not involved in the study, added that, “People tend to really focus on small intestinal bacteria overgrowth when it comes to hydrogen and methane production, but in reality, this is really a very agile day-to-day, meal-to-meal responsiveness.
“It’s a different paradigm,” he continued. “I’d also like to see more data as to why we see the diurnal rhythm” and whether potential factors such as intestinal transit times are playing a role.
Singh reported receiving royalties from UpToDate. Staller reported receiving research support from Ardelyx and Restasis and serving as a consultant to Anji, Ardelyx, GI Supply, Mahana, Restasis, and Sanofi. Funding associated with the study was not available at the time of publication.
A version of this article appeared on Medscape.com.
PHILADELPHIA — , according to a new study.
The low FODMAP diet is the most evidence-based dietary therapy for patients with IBS, but we know that “only about 50% of our patients respond to it,” said principal investigator Prashant Singh, MD, assistant professor at the University of Michigan in Ann Arbor, Michigan. “Exhaled breath gases represent bacterial fermentation of dietary carbohydrates. These measurements could provide a simple biomarker for response to low FODMAP diets.”
Even before starting the low FODMAP diet, “you could see notable differences in breath test patterns between responders and nonresponders,” he said. “We saw that low FODMAP responders had higher hydrogen (H2) and lower methane (CH4) at baseline than nonresponders and had a greater drop in hydrogen following FODMAP restriction vs nonresponders.”
He added that these results imply that responders to this diet may exhibit differences in baseline microbiota composition regarding saccharolytic capacity and/or methanogens.
Singh presented the findings at the American College of Gastroenterology (ACG) 2024 Annual Scientific Meeting.
Breaths That Can Predict Response
To determine if pre-intervention non-fasting breath patterns are associated with a clinical response to low FODMAP diets, Singh and colleagues enrolled 284 self-selected participants (mean age, 45.2 years) with mild to moderate gastrointestinal (GI) symptoms. Participants used an app-connected breath analyzer to record hourly, non-fasting H2 and CH4 levels during waking hours, in addition to logging meal content and symptom severity (bloating, abdominal pain, and flatulence) on a 0-10 scale.
Patients were directed to consume their habitual diet for 1 week, before following an app-directed low FODMAP diet for 1 week. Responders were defined as those with a ≥ 30% reduction in at least one mean symptom score. The researchers then compared average hourly H2 and CH4 levels and symptom scores at baseline between low FODMAP diet responders and nonresponders.
Of the participants, 111 were classified as responders and 173 as nonresponders. There were no significant differences between the groups in gender, age, body mass index, or FODMAP per calorie.
Following FODMAP restriction, responders had consistently lower abdominal pain throughout the day and lower bloating and flatulence predominantly in the latter part of the day. Nonresponders experienced no significant changes in key abdominal symptoms after adopting the low FODMAP diet.
The researchers found that breath tests taken at baseline revealed predictive trends between the groups, even though average FODMAP consumption did not significantly differ between them. Baseline H2 levels were higher among responders than among nonresponders, especially in the morning and evening. However, responders had lower baseline CH4 levels throughout the day.
Following FODMAP restrictions, responders had a significant drop in non-fasting H2 but not CH4, whereas nonresponders did not have a significant drop in either.
The study was limited by the fact that participants were not clinically diagnosed with IBS, their GI symptoms were mild overall, and no data were available on stool consistency/frequency or fecal microbiome composition for correlation with exhaled breath gas levels.
A Potential New Biomarker
Session co-moderator Kyle Staller, MD, MPH, director of the Gastrointestinal Motility Laboratory at Mass General and associate professor of medicine at Harvard Medical School in Boston, Massachusetts, said in an interview that if validated, these findings provide hope for better directing low FODMAP diets to those patients who may benefit.
There are some patients who may or may not respond to a FODMAP diet, for reasons we don’t yet know, possibly related to fermentation of gas, and it’s helpful to know before starting treatment, he said. It may help us with more of “a precision medicine approach before we really torture people with diets that can be very difficult to adhere to.”
Staller, who was not involved in the study, added that, “People tend to really focus on small intestinal bacteria overgrowth when it comes to hydrogen and methane production, but in reality, this is really a very agile day-to-day, meal-to-meal responsiveness.
“It’s a different paradigm,” he continued. “I’d also like to see more data as to why we see the diurnal rhythm” and whether potential factors such as intestinal transit times are playing a role.
Singh reported receiving royalties from UpToDate. Staller reported receiving research support from Ardelyx and Restasis and serving as a consultant to Anji, Ardelyx, GI Supply, Mahana, Restasis, and Sanofi. Funding associated with the study was not available at the time of publication.
A version of this article appeared on Medscape.com.
PHILADELPHIA — , according to a new study.
The low FODMAP diet is the most evidence-based dietary therapy for patients with IBS, but we know that “only about 50% of our patients respond to it,” said principal investigator Prashant Singh, MD, assistant professor at the University of Michigan in Ann Arbor, Michigan. “Exhaled breath gases represent bacterial fermentation of dietary carbohydrates. These measurements could provide a simple biomarker for response to low FODMAP diets.”
Even before starting the low FODMAP diet, “you could see notable differences in breath test patterns between responders and nonresponders,” he said. “We saw that low FODMAP responders had higher hydrogen (H2) and lower methane (CH4) at baseline than nonresponders and had a greater drop in hydrogen following FODMAP restriction vs nonresponders.”
He added that these results imply that responders to this diet may exhibit differences in baseline microbiota composition regarding saccharolytic capacity and/or methanogens.
Singh presented the findings at the American College of Gastroenterology (ACG) 2024 Annual Scientific Meeting.
Breaths That Can Predict Response
To determine if pre-intervention non-fasting breath patterns are associated with a clinical response to low FODMAP diets, Singh and colleagues enrolled 284 self-selected participants (mean age, 45.2 years) with mild to moderate gastrointestinal (GI) symptoms. Participants used an app-connected breath analyzer to record hourly, non-fasting H2 and CH4 levels during waking hours, in addition to logging meal content and symptom severity (bloating, abdominal pain, and flatulence) on a 0-10 scale.
Patients were directed to consume their habitual diet for 1 week, before following an app-directed low FODMAP diet for 1 week. Responders were defined as those with a ≥ 30% reduction in at least one mean symptom score. The researchers then compared average hourly H2 and CH4 levels and symptom scores at baseline between low FODMAP diet responders and nonresponders.
Of the participants, 111 were classified as responders and 173 as nonresponders. There were no significant differences between the groups in gender, age, body mass index, or FODMAP per calorie.
Following FODMAP restriction, responders had consistently lower abdominal pain throughout the day and lower bloating and flatulence predominantly in the latter part of the day. Nonresponders experienced no significant changes in key abdominal symptoms after adopting the low FODMAP diet.
The researchers found that breath tests taken at baseline revealed predictive trends between the groups, even though average FODMAP consumption did not significantly differ between them. Baseline H2 levels were higher among responders than among nonresponders, especially in the morning and evening. However, responders had lower baseline CH4 levels throughout the day.
Following FODMAP restrictions, responders had a significant drop in non-fasting H2 but not CH4, whereas nonresponders did not have a significant drop in either.
The study was limited by the fact that participants were not clinically diagnosed with IBS, their GI symptoms were mild overall, and no data were available on stool consistency/frequency or fecal microbiome composition for correlation with exhaled breath gas levels.
A Potential New Biomarker
Session co-moderator Kyle Staller, MD, MPH, director of the Gastrointestinal Motility Laboratory at Mass General and associate professor of medicine at Harvard Medical School in Boston, Massachusetts, said in an interview that if validated, these findings provide hope for better directing low FODMAP diets to those patients who may benefit.
There are some patients who may or may not respond to a FODMAP diet, for reasons we don’t yet know, possibly related to fermentation of gas, and it’s helpful to know before starting treatment, he said. It may help us with more of “a precision medicine approach before we really torture people with diets that can be very difficult to adhere to.”
Staller, who was not involved in the study, added that, “People tend to really focus on small intestinal bacteria overgrowth when it comes to hydrogen and methane production, but in reality, this is really a very agile day-to-day, meal-to-meal responsiveness.
“It’s a different paradigm,” he continued. “I’d also like to see more data as to why we see the diurnal rhythm” and whether potential factors such as intestinal transit times are playing a role.
Singh reported receiving royalties from UpToDate. Staller reported receiving research support from Ardelyx and Restasis and serving as a consultant to Anji, Ardelyx, GI Supply, Mahana, Restasis, and Sanofi. Funding associated with the study was not available at the time of publication.
A version of this article appeared on Medscape.com.
FROM ACG 2024
Ultraprocessed Foods Associated With Relapse Risk in Crohn’s Disease
VIENNA —
Certain subgroups of UPFs, specifically bread, pastries, and starch as well as oil and spreads, exhibited the strongest association with relapse risks of approximately threefold.
“In addition to treating active inflammatory bowel disease (IBD), we want to maintain remission for the long term,” Chen Sarbagili Shabat, PhD, clinical dietitian from Tel Aviv Medical Center in Israel, said in an interview. “It’s highly important. We know environmental factors are associated with the disease, which is why we can treat active disease with diet. Likewise, we can manage CD in a remission state with diet.”
This is the first prospective study of this particular level of UPFs in people with Crohn’s disease who are in remission, noted Shabat, who presented the findings at United European Gastroenterology (UEG) Week 2024.
Previously, a meta-analysis of prospective cohort studies showed that a diet high in UPFs is associated with a 70% increased risk for development of CD, and a longitudinal study showed that “Western” dietary patterns were associated with relapse risk in patients with IBD, Shabat reported.
Effect of High vs Low Intake of UPFs
The current single-center, prospective cohort study, followed 111 patients with CD every 3 months until relapse for up to 1 year.
Participants were aged 18-75 years (mean age, 38 years), with a median disease duration of 8.7 years. They were required to have maintained steroid-free clinical remission (Harvey-Bradshaw Index (HBI), < 5) for 3 months or more. The median duration of clinical remission at recruitment was 3 years.
Data collection included HBI level, medication type and dosage to ensure constant therapy and full compliance, and a stool sample for fecal calprotectin measurement.
The primary outcome comprised a clinical relapse HBI ≥ 5 over the 12-month follow-up or a change in disease activity requiring a change in medication, hospitalization, or any IBD-related surgery.
Participants were asked to complete a processed food questionnaire to assess the intake of UPFs and a food frequency questionnaire to assess the total intake of energy, macronutrients, and micronutrients. UPFs were divided into high and low intakes using a median cutoff of 3.6 servings/day.
The low intake group included 57 participants, and the high intake group included 54.
A total of 24 patients (21.6%) experienced a clinical relapse event, 7 in the low intake group vs 17 in the high intake group (hazard ratio [HR], 3.86; 95% CI, 1.30-11.47; P = .015 after adjustments).
In a subset of 97 patients with baseline fecal calprotectin measurements, 6 (n = 50) in the low intake group experienced a clinical relapse vs 15 (n = 47) in the high intake group (HR, 4.32; 95% CI, 1.36-13.73; P = .013 after adjustments).
Fecal calprotectin results were also suggestive of an association between high intake of UPFs and gut inflammation, Shabat reported.
Food Groups and Emulsifiers
UPFs were divided into subgroups: Bread, pastries, and starch; oils and spreads; ultraprocessed meat; sweet products and desserts; and ultraprocessed beverages.
The highest associations with relapse were in the subgroup of bread, pastries, and starch (HR, 3.37; 95% CI, 1.26-8.25) and the subgroup of oils and spreads (HR, 2.76; 95% CI, 1.02-7.45).
“The selection of healthy food is highly important, especially since we know that certain food ingredients can contribute to the pathogenesis of CD,” Shabat said. Patients can use partial enteral nutrition to provide 40%-50% of daily caloric intake in order to maintain remission, but she acknowledged it can be really difficult to adhere to.
She concluded by asserting that the study results, along with future research, should contribute to establishing nutritional guidelines to reduce UPF consumption in patients with CD in order to maintain remission.
Commenting on the study, Kevin Whelan, PhD, professor of dietetics and head of the Department of Nutritional Sciences at King’s College London in England, said that he was intrigued by the subgroup analysis that showed breads, pastries, oils, and spreads as having the strongest association with relapse risk.
He also remarked that these foods almost ubiquitously contain emulsifiers, and so the association might have less to do with UPFs in general and more to do with emulsifiers.
Concurring, Shabat noted that, while emulsifiers can negatively influence the microbiota and the gut barrier function, as well as contribute to intestinal inflammation, further mechanistic studies are required to understand these effects.
We need to determine if all additives have the same effect on the inflammatory process and also need studies looking at UPFs alone, she added.
Shabat reported receiving personal fees from Nestle Health Science (Wolfson Medical Center IP) for consulting and speaking and from Takeda and Ferring for speaking. Whelan reported no relevant disclosures.
A version of this article first appeared on Medscape.com.
VIENNA —
Certain subgroups of UPFs, specifically bread, pastries, and starch as well as oil and spreads, exhibited the strongest association with relapse risks of approximately threefold.
“In addition to treating active inflammatory bowel disease (IBD), we want to maintain remission for the long term,” Chen Sarbagili Shabat, PhD, clinical dietitian from Tel Aviv Medical Center in Israel, said in an interview. “It’s highly important. We know environmental factors are associated with the disease, which is why we can treat active disease with diet. Likewise, we can manage CD in a remission state with diet.”
This is the first prospective study of this particular level of UPFs in people with Crohn’s disease who are in remission, noted Shabat, who presented the findings at United European Gastroenterology (UEG) Week 2024.
Previously, a meta-analysis of prospective cohort studies showed that a diet high in UPFs is associated with a 70% increased risk for development of CD, and a longitudinal study showed that “Western” dietary patterns were associated with relapse risk in patients with IBD, Shabat reported.
Effect of High vs Low Intake of UPFs
The current single-center, prospective cohort study, followed 111 patients with CD every 3 months until relapse for up to 1 year.
Participants were aged 18-75 years (mean age, 38 years), with a median disease duration of 8.7 years. They were required to have maintained steroid-free clinical remission (Harvey-Bradshaw Index (HBI), < 5) for 3 months or more. The median duration of clinical remission at recruitment was 3 years.
Data collection included HBI level, medication type and dosage to ensure constant therapy and full compliance, and a stool sample for fecal calprotectin measurement.
The primary outcome comprised a clinical relapse HBI ≥ 5 over the 12-month follow-up or a change in disease activity requiring a change in medication, hospitalization, or any IBD-related surgery.
Participants were asked to complete a processed food questionnaire to assess the intake of UPFs and a food frequency questionnaire to assess the total intake of energy, macronutrients, and micronutrients. UPFs were divided into high and low intakes using a median cutoff of 3.6 servings/day.
The low intake group included 57 participants, and the high intake group included 54.
A total of 24 patients (21.6%) experienced a clinical relapse event, 7 in the low intake group vs 17 in the high intake group (hazard ratio [HR], 3.86; 95% CI, 1.30-11.47; P = .015 after adjustments).
In a subset of 97 patients with baseline fecal calprotectin measurements, 6 (n = 50) in the low intake group experienced a clinical relapse vs 15 (n = 47) in the high intake group (HR, 4.32; 95% CI, 1.36-13.73; P = .013 after adjustments).
Fecal calprotectin results were also suggestive of an association between high intake of UPFs and gut inflammation, Shabat reported.
Food Groups and Emulsifiers
UPFs were divided into subgroups: Bread, pastries, and starch; oils and spreads; ultraprocessed meat; sweet products and desserts; and ultraprocessed beverages.
The highest associations with relapse were in the subgroup of bread, pastries, and starch (HR, 3.37; 95% CI, 1.26-8.25) and the subgroup of oils and spreads (HR, 2.76; 95% CI, 1.02-7.45).
“The selection of healthy food is highly important, especially since we know that certain food ingredients can contribute to the pathogenesis of CD,” Shabat said. Patients can use partial enteral nutrition to provide 40%-50% of daily caloric intake in order to maintain remission, but she acknowledged it can be really difficult to adhere to.
She concluded by asserting that the study results, along with future research, should contribute to establishing nutritional guidelines to reduce UPF consumption in patients with CD in order to maintain remission.
Commenting on the study, Kevin Whelan, PhD, professor of dietetics and head of the Department of Nutritional Sciences at King’s College London in England, said that he was intrigued by the subgroup analysis that showed breads, pastries, oils, and spreads as having the strongest association with relapse risk.
He also remarked that these foods almost ubiquitously contain emulsifiers, and so the association might have less to do with UPFs in general and more to do with emulsifiers.
Concurring, Shabat noted that, while emulsifiers can negatively influence the microbiota and the gut barrier function, as well as contribute to intestinal inflammation, further mechanistic studies are required to understand these effects.
We need to determine if all additives have the same effect on the inflammatory process and also need studies looking at UPFs alone, she added.
Shabat reported receiving personal fees from Nestle Health Science (Wolfson Medical Center IP) for consulting and speaking and from Takeda and Ferring for speaking. Whelan reported no relevant disclosures.
A version of this article first appeared on Medscape.com.
VIENNA —
Certain subgroups of UPFs, specifically bread, pastries, and starch as well as oil and spreads, exhibited the strongest association with relapse risks of approximately threefold.
“In addition to treating active inflammatory bowel disease (IBD), we want to maintain remission for the long term,” Chen Sarbagili Shabat, PhD, clinical dietitian from Tel Aviv Medical Center in Israel, said in an interview. “It’s highly important. We know environmental factors are associated with the disease, which is why we can treat active disease with diet. Likewise, we can manage CD in a remission state with diet.”
This is the first prospective study of this particular level of UPFs in people with Crohn’s disease who are in remission, noted Shabat, who presented the findings at United European Gastroenterology (UEG) Week 2024.
Previously, a meta-analysis of prospective cohort studies showed that a diet high in UPFs is associated with a 70% increased risk for development of CD, and a longitudinal study showed that “Western” dietary patterns were associated with relapse risk in patients with IBD, Shabat reported.
Effect of High vs Low Intake of UPFs
The current single-center, prospective cohort study, followed 111 patients with CD every 3 months until relapse for up to 1 year.
Participants were aged 18-75 years (mean age, 38 years), with a median disease duration of 8.7 years. They were required to have maintained steroid-free clinical remission (Harvey-Bradshaw Index (HBI), < 5) for 3 months or more. The median duration of clinical remission at recruitment was 3 years.
Data collection included HBI level, medication type and dosage to ensure constant therapy and full compliance, and a stool sample for fecal calprotectin measurement.
The primary outcome comprised a clinical relapse HBI ≥ 5 over the 12-month follow-up or a change in disease activity requiring a change in medication, hospitalization, or any IBD-related surgery.
Participants were asked to complete a processed food questionnaire to assess the intake of UPFs and a food frequency questionnaire to assess the total intake of energy, macronutrients, and micronutrients. UPFs were divided into high and low intakes using a median cutoff of 3.6 servings/day.
The low intake group included 57 participants, and the high intake group included 54.
A total of 24 patients (21.6%) experienced a clinical relapse event, 7 in the low intake group vs 17 in the high intake group (hazard ratio [HR], 3.86; 95% CI, 1.30-11.47; P = .015 after adjustments).
In a subset of 97 patients with baseline fecal calprotectin measurements, 6 (n = 50) in the low intake group experienced a clinical relapse vs 15 (n = 47) in the high intake group (HR, 4.32; 95% CI, 1.36-13.73; P = .013 after adjustments).
Fecal calprotectin results were also suggestive of an association between high intake of UPFs and gut inflammation, Shabat reported.
Food Groups and Emulsifiers
UPFs were divided into subgroups: Bread, pastries, and starch; oils and spreads; ultraprocessed meat; sweet products and desserts; and ultraprocessed beverages.
The highest associations with relapse were in the subgroup of bread, pastries, and starch (HR, 3.37; 95% CI, 1.26-8.25) and the subgroup of oils and spreads (HR, 2.76; 95% CI, 1.02-7.45).
“The selection of healthy food is highly important, especially since we know that certain food ingredients can contribute to the pathogenesis of CD,” Shabat said. Patients can use partial enteral nutrition to provide 40%-50% of daily caloric intake in order to maintain remission, but she acknowledged it can be really difficult to adhere to.
She concluded by asserting that the study results, along with future research, should contribute to establishing nutritional guidelines to reduce UPF consumption in patients with CD in order to maintain remission.
Commenting on the study, Kevin Whelan, PhD, professor of dietetics and head of the Department of Nutritional Sciences at King’s College London in England, said that he was intrigued by the subgroup analysis that showed breads, pastries, oils, and spreads as having the strongest association with relapse risk.
He also remarked that these foods almost ubiquitously contain emulsifiers, and so the association might have less to do with UPFs in general and more to do with emulsifiers.
Concurring, Shabat noted that, while emulsifiers can negatively influence the microbiota and the gut barrier function, as well as contribute to intestinal inflammation, further mechanistic studies are required to understand these effects.
We need to determine if all additives have the same effect on the inflammatory process and also need studies looking at UPFs alone, she added.
Shabat reported receiving personal fees from Nestle Health Science (Wolfson Medical Center IP) for consulting and speaking and from Takeda and Ferring for speaking. Whelan reported no relevant disclosures.
A version of this article first appeared on Medscape.com.
FROM UEG 2024
Help Your Patients Reap the Benefits of Plant-Based Diets
Research pooled from nearly 100 studies has indicated that people who adhere to a vegan diet (ie, completely devoid of animal products) or a vegetarian diet (ie, devoid of meat, but may include dairy and eggs) are able to ward off some chronic diseases, such as cardiovascular disease, optimize glycemic control, and decrease their risk for cancer compared with those who consume omnivorous diets.
Vegan and vegetarian diets, or flexitarian diets — which are less reliant on animal protein than the standard US diet but do not completely exclude meat, fish, eggs, or dairy — may promote homeostasis and decrease inflammation by providing more fiber, antioxidants, and unsaturated fatty acids than the typical Western diet.
Inflammation and Obesity
Adipose tissue is a major producer of pro-inflammatory cytokines like interleukin (IL)-6, whose presence then triggers a rush of acute-phase reactants such as C-reactive protein (CRP) by the liver. This process develops into chronic low-grade inflammation that can increase a person’s chances of developing diabetes, cardiovascular disease, kidney disease, metabolic syndrome, and related complications.
Adopting a plant-based diet can improve markers of chronic low-grade inflammation that can lead to chronic disease and worsen existent chronic disease. A meta-analysis of 29 studies encompassing nearly 2700 participants found that initiation of a plant-based diet showed significant improvement in CRP, IL-6, and soluble intercellular adhesion molecule 1.
If we want to prevent these inflammatory disease states and their complications, the obvious response is to counsel patients to avoid excessive weight gain or to lose weight if obesity is their baseline. This can be tough for some patients, but it is nonetheless an important step in chronic disease prevention and management.
Plant-Based Diet for Type 2 Diabetes
According to a review of nine studies of patients living with type 2 diabetes who adhered to a plant-based diet, all but one found that this approach led to significantly lower A1c values than those seen in control groups. Six of the included studies reported that participants were able to decrease or discontinue medications for the management of diabetes. Researchers across all included studies also noted a decrease in total cholesterol, low-density lipoprotein cholesterol, and triglycerides, as well as increased weight loss in participants in each intervention group.
Such improvements are probably the result of the increase in fiber intake that occurs with a plant-based diet. A high-fiber diet is known to promote improved glucose and lipid metabolism as well as weight loss.
It is also worth noting that participants in the intervention groups also experienced improvements in depression and less chronic pain than did those in the control groups.
Plant-Based Diet for Chronic Kidney Disease (CKD)
Although the use of a plant-based diet in the prevention of CKD is well documented, adopting such diets for the treatment of CKD may intimidate both patients and practitioners owing to the high potassium and phosphorus content of many fruits and vegetables.
However, research indicates that the bioavailability of both potassium and phosphorus is lower in plant-based, whole foods than in preservatives and the highly processed food items that incorporate them. This makes a plant-based diet more viable than previously thought.
Diets rich in vegetables, whole grains, nuts, and legumes have been shown to decrease dietary acid load, both preventing and treating metabolic acidosis. Such diets have also been shown to decrease blood pressure and the risk for a decline in estimated glomerular filtration rate. This type of diet would also prioritize the unsaturated fatty acids and fiber-rich proteins such as avocados, beans, and nuts shown to improve dyslipidemia, which may occur alongside CKD.
Realistic Options for Patients on Medical Diets
There is one question that I always seem to get from when recommending a plant-based diet: “These patients already have so many restrictions. Why would you add more?” And my answer is also always the same: I don’t.
I rarely, if ever, recommend completely cutting out any food item or food group. Instead, I ask the patient to increase their intake of plant-based foods and only limit highly processed foods and fatty meats. By shifting a patient’s focus to beans; nuts; and low-carbohydrate, high-fiber fruits and vegetables, I am often opening up a whole new world of possibilities.
Instead of a sandwich with low-sodium turkey and cheese on white bread with a side of unsalted pretzels, I recommend a caprese salad with blueberries and almonds or a Southwest salad with black beans, corn, and avocado. I don’t encourage my patients to skip the foods that they love, but instead to only think about all the delicious plant-based options that will provide them with more than just calories.
Meat, dairy, seafood, and eggs can certainly be a part of a healthy diet, but what if our chronically ill patients, especially those with diabetes, had more options than just grilled chicken and green beans for every meal? What if we focus on decreasing dietary restrictions, incorporating a variety of nourishing foods, and educating our patients, instead of on portion control and moderation?
This is how I choose to incorporate plant-based diets into my practice to treat and prevent these chronic inflammatory conditions and promote sustainable, realistic change in my clients’ health.
Brandy Winfree Root, a renal dietitian in private practice in Mary Esther, Florida, has disclosed no relevant financial relationships.
A version of this article appeared on Medscape.com.
Research pooled from nearly 100 studies has indicated that people who adhere to a vegan diet (ie, completely devoid of animal products) or a vegetarian diet (ie, devoid of meat, but may include dairy and eggs) are able to ward off some chronic diseases, such as cardiovascular disease, optimize glycemic control, and decrease their risk for cancer compared with those who consume omnivorous diets.
Vegan and vegetarian diets, or flexitarian diets — which are less reliant on animal protein than the standard US diet but do not completely exclude meat, fish, eggs, or dairy — may promote homeostasis and decrease inflammation by providing more fiber, antioxidants, and unsaturated fatty acids than the typical Western diet.
Inflammation and Obesity
Adipose tissue is a major producer of pro-inflammatory cytokines like interleukin (IL)-6, whose presence then triggers a rush of acute-phase reactants such as C-reactive protein (CRP) by the liver. This process develops into chronic low-grade inflammation that can increase a person’s chances of developing diabetes, cardiovascular disease, kidney disease, metabolic syndrome, and related complications.
Adopting a plant-based diet can improve markers of chronic low-grade inflammation that can lead to chronic disease and worsen existent chronic disease. A meta-analysis of 29 studies encompassing nearly 2700 participants found that initiation of a plant-based diet showed significant improvement in CRP, IL-6, and soluble intercellular adhesion molecule 1.
If we want to prevent these inflammatory disease states and their complications, the obvious response is to counsel patients to avoid excessive weight gain or to lose weight if obesity is their baseline. This can be tough for some patients, but it is nonetheless an important step in chronic disease prevention and management.
Plant-Based Diet for Type 2 Diabetes
According to a review of nine studies of patients living with type 2 diabetes who adhered to a plant-based diet, all but one found that this approach led to significantly lower A1c values than those seen in control groups. Six of the included studies reported that participants were able to decrease or discontinue medications for the management of diabetes. Researchers across all included studies also noted a decrease in total cholesterol, low-density lipoprotein cholesterol, and triglycerides, as well as increased weight loss in participants in each intervention group.
Such improvements are probably the result of the increase in fiber intake that occurs with a plant-based diet. A high-fiber diet is known to promote improved glucose and lipid metabolism as well as weight loss.
It is also worth noting that participants in the intervention groups also experienced improvements in depression and less chronic pain than did those in the control groups.
Plant-Based Diet for Chronic Kidney Disease (CKD)
Although the use of a plant-based diet in the prevention of CKD is well documented, adopting such diets for the treatment of CKD may intimidate both patients and practitioners owing to the high potassium and phosphorus content of many fruits and vegetables.
However, research indicates that the bioavailability of both potassium and phosphorus is lower in plant-based, whole foods than in preservatives and the highly processed food items that incorporate them. This makes a plant-based diet more viable than previously thought.
Diets rich in vegetables, whole grains, nuts, and legumes have been shown to decrease dietary acid load, both preventing and treating metabolic acidosis. Such diets have also been shown to decrease blood pressure and the risk for a decline in estimated glomerular filtration rate. This type of diet would also prioritize the unsaturated fatty acids and fiber-rich proteins such as avocados, beans, and nuts shown to improve dyslipidemia, which may occur alongside CKD.
Realistic Options for Patients on Medical Diets
There is one question that I always seem to get from when recommending a plant-based diet: “These patients already have so many restrictions. Why would you add more?” And my answer is also always the same: I don’t.
I rarely, if ever, recommend completely cutting out any food item or food group. Instead, I ask the patient to increase their intake of plant-based foods and only limit highly processed foods and fatty meats. By shifting a patient’s focus to beans; nuts; and low-carbohydrate, high-fiber fruits and vegetables, I am often opening up a whole new world of possibilities.
Instead of a sandwich with low-sodium turkey and cheese on white bread with a side of unsalted pretzels, I recommend a caprese salad with blueberries and almonds or a Southwest salad with black beans, corn, and avocado. I don’t encourage my patients to skip the foods that they love, but instead to only think about all the delicious plant-based options that will provide them with more than just calories.
Meat, dairy, seafood, and eggs can certainly be a part of a healthy diet, but what if our chronically ill patients, especially those with diabetes, had more options than just grilled chicken and green beans for every meal? What if we focus on decreasing dietary restrictions, incorporating a variety of nourishing foods, and educating our patients, instead of on portion control and moderation?
This is how I choose to incorporate plant-based diets into my practice to treat and prevent these chronic inflammatory conditions and promote sustainable, realistic change in my clients’ health.
Brandy Winfree Root, a renal dietitian in private practice in Mary Esther, Florida, has disclosed no relevant financial relationships.
A version of this article appeared on Medscape.com.
Research pooled from nearly 100 studies has indicated that people who adhere to a vegan diet (ie, completely devoid of animal products) or a vegetarian diet (ie, devoid of meat, but may include dairy and eggs) are able to ward off some chronic diseases, such as cardiovascular disease, optimize glycemic control, and decrease their risk for cancer compared with those who consume omnivorous diets.
Vegan and vegetarian diets, or flexitarian diets — which are less reliant on animal protein than the standard US diet but do not completely exclude meat, fish, eggs, or dairy — may promote homeostasis and decrease inflammation by providing more fiber, antioxidants, and unsaturated fatty acids than the typical Western diet.
Inflammation and Obesity
Adipose tissue is a major producer of pro-inflammatory cytokines like interleukin (IL)-6, whose presence then triggers a rush of acute-phase reactants such as C-reactive protein (CRP) by the liver. This process develops into chronic low-grade inflammation that can increase a person’s chances of developing diabetes, cardiovascular disease, kidney disease, metabolic syndrome, and related complications.
Adopting a plant-based diet can improve markers of chronic low-grade inflammation that can lead to chronic disease and worsen existent chronic disease. A meta-analysis of 29 studies encompassing nearly 2700 participants found that initiation of a plant-based diet showed significant improvement in CRP, IL-6, and soluble intercellular adhesion molecule 1.
If we want to prevent these inflammatory disease states and their complications, the obvious response is to counsel patients to avoid excessive weight gain or to lose weight if obesity is their baseline. This can be tough for some patients, but it is nonetheless an important step in chronic disease prevention and management.
Plant-Based Diet for Type 2 Diabetes
According to a review of nine studies of patients living with type 2 diabetes who adhered to a plant-based diet, all but one found that this approach led to significantly lower A1c values than those seen in control groups. Six of the included studies reported that participants were able to decrease or discontinue medications for the management of diabetes. Researchers across all included studies also noted a decrease in total cholesterol, low-density lipoprotein cholesterol, and triglycerides, as well as increased weight loss in participants in each intervention group.
Such improvements are probably the result of the increase in fiber intake that occurs with a plant-based diet. A high-fiber diet is known to promote improved glucose and lipid metabolism as well as weight loss.
It is also worth noting that participants in the intervention groups also experienced improvements in depression and less chronic pain than did those in the control groups.
Plant-Based Diet for Chronic Kidney Disease (CKD)
Although the use of a plant-based diet in the prevention of CKD is well documented, adopting such diets for the treatment of CKD may intimidate both patients and practitioners owing to the high potassium and phosphorus content of many fruits and vegetables.
However, research indicates that the bioavailability of both potassium and phosphorus is lower in plant-based, whole foods than in preservatives and the highly processed food items that incorporate them. This makes a plant-based diet more viable than previously thought.
Diets rich in vegetables, whole grains, nuts, and legumes have been shown to decrease dietary acid load, both preventing and treating metabolic acidosis. Such diets have also been shown to decrease blood pressure and the risk for a decline in estimated glomerular filtration rate. This type of diet would also prioritize the unsaturated fatty acids and fiber-rich proteins such as avocados, beans, and nuts shown to improve dyslipidemia, which may occur alongside CKD.
Realistic Options for Patients on Medical Diets
There is one question that I always seem to get from when recommending a plant-based diet: “These patients already have so many restrictions. Why would you add more?” And my answer is also always the same: I don’t.
I rarely, if ever, recommend completely cutting out any food item or food group. Instead, I ask the patient to increase their intake of plant-based foods and only limit highly processed foods and fatty meats. By shifting a patient’s focus to beans; nuts; and low-carbohydrate, high-fiber fruits and vegetables, I am often opening up a whole new world of possibilities.
Instead of a sandwich with low-sodium turkey and cheese on white bread with a side of unsalted pretzels, I recommend a caprese salad with blueberries and almonds or a Southwest salad with black beans, corn, and avocado. I don’t encourage my patients to skip the foods that they love, but instead to only think about all the delicious plant-based options that will provide them with more than just calories.
Meat, dairy, seafood, and eggs can certainly be a part of a healthy diet, but what if our chronically ill patients, especially those with diabetes, had more options than just grilled chicken and green beans for every meal? What if we focus on decreasing dietary restrictions, incorporating a variety of nourishing foods, and educating our patients, instead of on portion control and moderation?
This is how I choose to incorporate plant-based diets into my practice to treat and prevent these chronic inflammatory conditions and promote sustainable, realistic change in my clients’ health.
Brandy Winfree Root, a renal dietitian in private practice in Mary Esther, Florida, has disclosed no relevant financial relationships.
A version of this article appeared on Medscape.com.
How the Future of Medicine Will Revolve Around Our Gut
Meet your new patients.
You can’t see them, but trillions — maybe quadrillions — of them travel in and out of your practice every day. They’re hungry, mysterious, community-oriented, and small. Very, very small.
They’re the microbes occupying your current patients’ guts.
Someday soon, you’ll prescribe medicine not just for humans but also for these microbes.
“I am convinced in the future our medicine cabinets are going to have not just medications like a statin for treating us, but [also] pills that treat and inhibit an enzyme in our microbes and elicit a health benefit in some chronic disease,” said Stanley Hazen, MD, PhD, co-section head of Preventive Cardiology & Rehabilitation and director of the Center for Microbiome & Human Health at Cleveland Clinic, Cleveland, Ohio.
These trillions of microbes use our food to generate substances called metabolites that can protect or harm our health, with consequences reaching far beyond our gastrointestinal tracts.
Research has linked microbial metabolites to diabetes, cardiovascular disease, liver disease, obesity, high blood pressure, neurological disorders, depression, cancer, and more. Gastroenterologist Christopher Damman, MD, a clinical associate professor at the University of Washington Medical Center, Seattle, calls it a “growing theme” in microbiome science.
Now scientists are developing treatments targeting gut microbial pathways, designed to eliminate the bad metabolites and boost the good metabolites.
One close to human therapeutic intervention is an oral treatment from Dr. Hazen’s lab targeting the metabolite trimethylamine N-oxide (TMAO), a predictor of and contributor to both cardiovascular disease and chronic kidney disease. The drug, which blocks TMAO formation, is nearing clinical trials, Dr. Hazen said.
The advantage is safety. By targeting the microbe instead of, say, an enzyme, the host (your patient) must absorb little if any drug.
Implications for the future of medicine are huge. “Gut microbial pathways contribute to diabetes, obesity, virtually everything,” Dr. Hazen said. “Therapies that target gut microbiome processes will probably even be used for psychiatric disorders within, I’ll say, 10 or 20 years.”
The Science
About 100 trillion strains of bacteria live in our guts. As humans have evolved, so have they.
Between 70% and 90% come from the phyla Firmicutes and Bacteroidetes, with person-to-person variation shaped by genetics, environment, and lifestyle.
“Everyone’s microbiome is subtly different,” said Dr. Hazen. “So the combination of what they’re making is different. All these different biologically active compounds are influencing us in subtly different ways.”
How it works: When you eat, your microbes eat, breaking down food into metabolites that interact with the thin layer of epithelial cells lining your gut. Some can be absorbed through the lining and into your bloodstream, a phenomenon known as “leaky gut.” Once in your blood, they can trigger irritation and inflammation, potentially leading to a wide variety of health issues, from gas and bloating to autoimmune conditions and mood disorders.
“On the other side of the epithelial lining, you have some of the largest concentrations of immune cells,” said Narendra Kumar, PhD, associate professor of pharmaceutical sciences at Texas A&M University, College Station, Texas.
Metabolites can influence how these immune cells work, possibly explaining why each person’s immune system behaves distinctively.
Of the 1000-plus metabolites linked to the gut microbiome, scientists have identified several that matter.
Short-chain fatty acids. When we eat fiber, colon bacteria ferment it into the beneficial short-chain fatty acids acetate, propionate, and butyrate. These bind to receptors in muscle, liver, and fat tissue, affecting the secretion of gut hormones and peptides related to appetite, inflammation, energy expenditure, and fat oxidation.
Butyrate has been linked to health benefits. It supports the integrity of the gut’s lining, stifling pathogenic gut bacteria, fighting cancer-promoting inflammation, and protecting against obesity and diabetes. It can function as a prebiotic, helping beneficial bacteria thrive. And recent studies linked an abundance of butyrate-producing bacteria with reduced bone fracture risk and hospitalization for infectious disease.
TMAO and phenylacetylglutamine. When we eat foods rich in animal proteins — think eggs, milk, fish, and especially red meat — some gut bacteria convert nutrients like choline and L-carnitine into TMAO and phenylalanine into phenylacetylglutamine. Research conducted by Dr. Hazen’s lab and replicated by others has linked both metabolites to heart problems.
In a landmark study from Dr. Hazen’s group, healthy adults who went on to develop coronary artery disease had significantly higher plasma TMAO levels than those who did not wind up with the condition. The association remained strong, even after controlling for risk factors like age, sex, smoking, high blood pressure, and high cholesterol.
In preclinical studies, elevated TMAO enhanced cardiovascular disease. TMAO-producing microbes also accentuated cardiovascular disease phenotypes in mouse models, while blocking these pathways inhibited the phenotypes.
Research suggests TMAO may harm cardiomyocytes (cells that contract and relax the heart) in dozens of ways, such as activating the expression of proteins to promote hypertrophy and fibrosis, decreasing mitochondrial function, and disrupting calcium signaling.
Another study linked phenylacetylglutamine levels to cardiac event risk in patients with heart failure. Recent mechanistic investigations suggest the metabolite alters signaling in a beta-adrenergic receptor involved in our fight-or-flight response, said Hazen.
“It’s like a rheostat on the light switch, a dimmer switch, and it’s what’s called a negative allosteric modulator,” he said. “It’s the first time that this type of behavior has ever been shown to be present for a gut microbial metabolite and a host receptor.”
Tryptophan metabolites. Microbes in your colon can convert the amino acid tryptophan, also found in animal-based foods, into neurotransmitters like serotonin and melatonin.
“The enteric nervous system, the nervous system around the gut, is immense,” said James Versalovic, MD, PhD, professor of pathology and immunology at Baylor College of Medicine, Houston. “The gut-brain axis has become a very fertile area of research.”
Lesser-known tryptophan metabolites — like indole, tryptamine, and indoleethanol — have been linked to benefits like fortifying the gut barrier, promoting the release of glucagon-like peptide 1 to reduce appetite, and protecting the liver from hepatitis. However, indole can also spur the production of indoxyl sulfate, a toxin linked to chronic kidney disease.
Bile acid byproducts. Your gut bugs also feast on (and transform) bile acids before they reabsorb and travel back to the liver.
Research is gaining traction on these secondary bile acids, which can affect inflammation and immune function in helpful and harmful ways.
One area of interest is how microbes break down hormones in bile. A recent study from Harvard showed that gut microbes convert corticoid hormones in bile into progestins, which could affect postpartum depression risk. And researchers are exploring the estrobolome — a gut microbial community dedicated to breaking down estrogen into its active form so it can be reabsorbed.
“Depending on the bacteria that you have, more or less can be recirculated back into your blood,” said Beatriz Peñalver Bernabé, PhD, an assistant professor of biomedical engineering and urology at the University of Illinois Chicago. “So you may be producing the same amount of estrogen, but depending on the bacteria you have, the real free estrogen that can bind to your cells may be very different.”
The gut microbiome can also regulate testosterone, with studies showing microbial differences in men with high testosterone vs those with less.
What Patients Can Do Now
Advances in the field of microbiome research — and the related “gut health” wellness craze — have spawned all kinds of new microbiome-based products: Like over-the-counter probiotic supplements and at-home test kits, which let you send a stool sample for analysis to reveal microbiome health and personalized diet recommendations.
But the science behind these tests is still evolving, said Dr. Damman. “The clinical inferences and applications are still pretty limited.”
For most people, the first step to fostering healthier microbial metabolites is much simpler: Diversify your diet.
“A lot of folks are missing that diversity,” Dr. Damman said.
“Eat foods and experiment with foods that you might not eat all the time,” especially fruits, vegetables, nuts, seeds, and beans.
Another strategy: Eat foods with probiotic bacteria. “I view it as an insurance policy,” said Dr. Versalovic, “fortifying my gut with probiotics, with daily yogurt, for example, at breakfast.”
Fermented foods like kimchi and kombucha can also increase microbial diversity and can even contain health-promoting postbiotics, research shows.
As for probiotic supplements, the jury’s still out.
Certain strains of probiotic bacteria may be beneficial for some patients, like those with diarrhea, Crohn’s disease, and irritable bowel syndrome, according to World Gastroenterology Organisation guidelines.
As with other interventions, individual responses can vary. A Stanford study showed that some people with metabolic syndrome improved when taking a probiotic, while others didn’t. Both groups had key differences in gut bacteria and dietary habits.
For best results, such microbiome-based interventions will need to be personalized, experts say. And the technology to do that is coming sooner than you might think.
Microbiome’s Medical Future: ‘We Are on the Cusp of a New Era’
In just a few years, artificial intelligence (AI) models could predict gut microbial composition based on data such as dietary habits and household characteristics, Dr. Kumar said.
Advancements in metabolomics and bioinformatics could soon help physicians and patients personalize their treatment approaches, said Dr. Damman.
One focus will be on fortifying the gut with whatever it lacks.
“In those individuals where certain microbes are missing, (a) how could we add them back potentially in a rational, science-driven way, and (b) maybe some of those factors that the microbes are producing out the other ends, you could give directly,” said Dr. Damman.
For example, multiple companies make butyrate as a dietary supplement, although the research is too early to support widespread use. Another option could be eating something that spurs butyrate production. One small study found that a fiber supplement formulated to increase butyrate levels in the colon reduced participants’ systolic blood pressure by an average of six points.
Another option could be synbiotics, products that combine bacteria and the food source they feed on. “If you just give a diet-based therapy, it is not going to work as much. Because what if that diet needs certain bacteria to have these beneficial metabolites?” said Ashutosh Mangalam, PhD, associate professor of pathology at the University of Iowa Carver College of Medicine, Iowa City.
Dr. Mangalam studies links between bacterial metabolism of phytoestrogens in soy foods and multiple sclerosis (MS) development. He is using AI to understand differences in metabolites in patients with MS vs healthy controls to determine how to target them.
Gut microbial metabolites could also affect disease screening and intervention. What if gut microbe sequencing could predict a pregnant person’s risk of developing depression, something now assessed through simple questionnaires?
“Imagine that your doctor says, ‘Okay, give me a poop sample,’ ” Dr. Bernabé said. “Then they phenotype it, and then they put it in your electronic medical record, and they say, ‘Well, you have high likelihood of having a mood disorder down the line in your pregnancy. Why don’t we directly refer you to a provider now so you can follow up?’ ”
Research is already underway to understand how metabolites might be linked to pregnancy outcomes, complex regional pain syndrome, and anxiety. Researchers are also investigating whether supplementing our diets with things like prebiotic fibers, apple polyphenols, or tomato paste might influence metabolites. And fecal transplants that shift the gut microbiome and metabolites could have potential in diseases like unexplained atherosclerosis, post-COVID syndrome, and hidradenitis suppurativa.
Dr. Hazen’s discovery linking TMAO with cardiovascular risk has already changed clinical practice. A blood TMAO test can help identify patients at risk who may not have traditional risk factors. “Millions have been done,” Dr. Hazen said.
Meanwhile, his drug targeting the TMAO pathway inches closer to clinical trials.
“In an animal model, we elicit improvement in heart failure, renal disease, atherosclerosis, thrombosis, aortic aneurysm, and obesity,” Dr. Hazen said. The first clinical trials will focus on renal disease.
As with any drug, the road to approval takes time. And success is not guaranteed.
But Dr. Hazen for one is optimistic.
“We are on the cusp of a new era,” Dr. Hazen said. “Like when humans first discovered insulin and glucagon were hormones that impact sugar metabolism. We now recognize myriad new ‘hormones’ in the form of gut microbiome metabolites that impact our physiology and susceptibility to diseases.”
A version of this article first appeared on Medscape.com.
Meet your new patients.
You can’t see them, but trillions — maybe quadrillions — of them travel in and out of your practice every day. They’re hungry, mysterious, community-oriented, and small. Very, very small.
They’re the microbes occupying your current patients’ guts.
Someday soon, you’ll prescribe medicine not just for humans but also for these microbes.
“I am convinced in the future our medicine cabinets are going to have not just medications like a statin for treating us, but [also] pills that treat and inhibit an enzyme in our microbes and elicit a health benefit in some chronic disease,” said Stanley Hazen, MD, PhD, co-section head of Preventive Cardiology & Rehabilitation and director of the Center for Microbiome & Human Health at Cleveland Clinic, Cleveland, Ohio.
These trillions of microbes use our food to generate substances called metabolites that can protect or harm our health, with consequences reaching far beyond our gastrointestinal tracts.
Research has linked microbial metabolites to diabetes, cardiovascular disease, liver disease, obesity, high blood pressure, neurological disorders, depression, cancer, and more. Gastroenterologist Christopher Damman, MD, a clinical associate professor at the University of Washington Medical Center, Seattle, calls it a “growing theme” in microbiome science.
Now scientists are developing treatments targeting gut microbial pathways, designed to eliminate the bad metabolites and boost the good metabolites.
One close to human therapeutic intervention is an oral treatment from Dr. Hazen’s lab targeting the metabolite trimethylamine N-oxide (TMAO), a predictor of and contributor to both cardiovascular disease and chronic kidney disease. The drug, which blocks TMAO formation, is nearing clinical trials, Dr. Hazen said.
The advantage is safety. By targeting the microbe instead of, say, an enzyme, the host (your patient) must absorb little if any drug.
Implications for the future of medicine are huge. “Gut microbial pathways contribute to diabetes, obesity, virtually everything,” Dr. Hazen said. “Therapies that target gut microbiome processes will probably even be used for psychiatric disorders within, I’ll say, 10 or 20 years.”
The Science
About 100 trillion strains of bacteria live in our guts. As humans have evolved, so have they.
Between 70% and 90% come from the phyla Firmicutes and Bacteroidetes, with person-to-person variation shaped by genetics, environment, and lifestyle.
“Everyone’s microbiome is subtly different,” said Dr. Hazen. “So the combination of what they’re making is different. All these different biologically active compounds are influencing us in subtly different ways.”
How it works: When you eat, your microbes eat, breaking down food into metabolites that interact with the thin layer of epithelial cells lining your gut. Some can be absorbed through the lining and into your bloodstream, a phenomenon known as “leaky gut.” Once in your blood, they can trigger irritation and inflammation, potentially leading to a wide variety of health issues, from gas and bloating to autoimmune conditions and mood disorders.
“On the other side of the epithelial lining, you have some of the largest concentrations of immune cells,” said Narendra Kumar, PhD, associate professor of pharmaceutical sciences at Texas A&M University, College Station, Texas.
Metabolites can influence how these immune cells work, possibly explaining why each person’s immune system behaves distinctively.
Of the 1000-plus metabolites linked to the gut microbiome, scientists have identified several that matter.
Short-chain fatty acids. When we eat fiber, colon bacteria ferment it into the beneficial short-chain fatty acids acetate, propionate, and butyrate. These bind to receptors in muscle, liver, and fat tissue, affecting the secretion of gut hormones and peptides related to appetite, inflammation, energy expenditure, and fat oxidation.
Butyrate has been linked to health benefits. It supports the integrity of the gut’s lining, stifling pathogenic gut bacteria, fighting cancer-promoting inflammation, and protecting against obesity and diabetes. It can function as a prebiotic, helping beneficial bacteria thrive. And recent studies linked an abundance of butyrate-producing bacteria with reduced bone fracture risk and hospitalization for infectious disease.
TMAO and phenylacetylglutamine. When we eat foods rich in animal proteins — think eggs, milk, fish, and especially red meat — some gut bacteria convert nutrients like choline and L-carnitine into TMAO and phenylalanine into phenylacetylglutamine. Research conducted by Dr. Hazen’s lab and replicated by others has linked both metabolites to heart problems.
In a landmark study from Dr. Hazen’s group, healthy adults who went on to develop coronary artery disease had significantly higher plasma TMAO levels than those who did not wind up with the condition. The association remained strong, even after controlling for risk factors like age, sex, smoking, high blood pressure, and high cholesterol.
In preclinical studies, elevated TMAO enhanced cardiovascular disease. TMAO-producing microbes also accentuated cardiovascular disease phenotypes in mouse models, while blocking these pathways inhibited the phenotypes.
Research suggests TMAO may harm cardiomyocytes (cells that contract and relax the heart) in dozens of ways, such as activating the expression of proteins to promote hypertrophy and fibrosis, decreasing mitochondrial function, and disrupting calcium signaling.
Another study linked phenylacetylglutamine levels to cardiac event risk in patients with heart failure. Recent mechanistic investigations suggest the metabolite alters signaling in a beta-adrenergic receptor involved in our fight-or-flight response, said Hazen.
“It’s like a rheostat on the light switch, a dimmer switch, and it’s what’s called a negative allosteric modulator,” he said. “It’s the first time that this type of behavior has ever been shown to be present for a gut microbial metabolite and a host receptor.”
Tryptophan metabolites. Microbes in your colon can convert the amino acid tryptophan, also found in animal-based foods, into neurotransmitters like serotonin and melatonin.
“The enteric nervous system, the nervous system around the gut, is immense,” said James Versalovic, MD, PhD, professor of pathology and immunology at Baylor College of Medicine, Houston. “The gut-brain axis has become a very fertile area of research.”
Lesser-known tryptophan metabolites — like indole, tryptamine, and indoleethanol — have been linked to benefits like fortifying the gut barrier, promoting the release of glucagon-like peptide 1 to reduce appetite, and protecting the liver from hepatitis. However, indole can also spur the production of indoxyl sulfate, a toxin linked to chronic kidney disease.
Bile acid byproducts. Your gut bugs also feast on (and transform) bile acids before they reabsorb and travel back to the liver.
Research is gaining traction on these secondary bile acids, which can affect inflammation and immune function in helpful and harmful ways.
One area of interest is how microbes break down hormones in bile. A recent study from Harvard showed that gut microbes convert corticoid hormones in bile into progestins, which could affect postpartum depression risk. And researchers are exploring the estrobolome — a gut microbial community dedicated to breaking down estrogen into its active form so it can be reabsorbed.
“Depending on the bacteria that you have, more or less can be recirculated back into your blood,” said Beatriz Peñalver Bernabé, PhD, an assistant professor of biomedical engineering and urology at the University of Illinois Chicago. “So you may be producing the same amount of estrogen, but depending on the bacteria you have, the real free estrogen that can bind to your cells may be very different.”
The gut microbiome can also regulate testosterone, with studies showing microbial differences in men with high testosterone vs those with less.
What Patients Can Do Now
Advances in the field of microbiome research — and the related “gut health” wellness craze — have spawned all kinds of new microbiome-based products: Like over-the-counter probiotic supplements and at-home test kits, which let you send a stool sample for analysis to reveal microbiome health and personalized diet recommendations.
But the science behind these tests is still evolving, said Dr. Damman. “The clinical inferences and applications are still pretty limited.”
For most people, the first step to fostering healthier microbial metabolites is much simpler: Diversify your diet.
“A lot of folks are missing that diversity,” Dr. Damman said.
“Eat foods and experiment with foods that you might not eat all the time,” especially fruits, vegetables, nuts, seeds, and beans.
Another strategy: Eat foods with probiotic bacteria. “I view it as an insurance policy,” said Dr. Versalovic, “fortifying my gut with probiotics, with daily yogurt, for example, at breakfast.”
Fermented foods like kimchi and kombucha can also increase microbial diversity and can even contain health-promoting postbiotics, research shows.
As for probiotic supplements, the jury’s still out.
Certain strains of probiotic bacteria may be beneficial for some patients, like those with diarrhea, Crohn’s disease, and irritable bowel syndrome, according to World Gastroenterology Organisation guidelines.
As with other interventions, individual responses can vary. A Stanford study showed that some people with metabolic syndrome improved when taking a probiotic, while others didn’t. Both groups had key differences in gut bacteria and dietary habits.
For best results, such microbiome-based interventions will need to be personalized, experts say. And the technology to do that is coming sooner than you might think.
Microbiome’s Medical Future: ‘We Are on the Cusp of a New Era’
In just a few years, artificial intelligence (AI) models could predict gut microbial composition based on data such as dietary habits and household characteristics, Dr. Kumar said.
Advancements in metabolomics and bioinformatics could soon help physicians and patients personalize their treatment approaches, said Dr. Damman.
One focus will be on fortifying the gut with whatever it lacks.
“In those individuals where certain microbes are missing, (a) how could we add them back potentially in a rational, science-driven way, and (b) maybe some of those factors that the microbes are producing out the other ends, you could give directly,” said Dr. Damman.
For example, multiple companies make butyrate as a dietary supplement, although the research is too early to support widespread use. Another option could be eating something that spurs butyrate production. One small study found that a fiber supplement formulated to increase butyrate levels in the colon reduced participants’ systolic blood pressure by an average of six points.
Another option could be synbiotics, products that combine bacteria and the food source they feed on. “If you just give a diet-based therapy, it is not going to work as much. Because what if that diet needs certain bacteria to have these beneficial metabolites?” said Ashutosh Mangalam, PhD, associate professor of pathology at the University of Iowa Carver College of Medicine, Iowa City.
Dr. Mangalam studies links between bacterial metabolism of phytoestrogens in soy foods and multiple sclerosis (MS) development. He is using AI to understand differences in metabolites in patients with MS vs healthy controls to determine how to target them.
Gut microbial metabolites could also affect disease screening and intervention. What if gut microbe sequencing could predict a pregnant person’s risk of developing depression, something now assessed through simple questionnaires?
“Imagine that your doctor says, ‘Okay, give me a poop sample,’ ” Dr. Bernabé said. “Then they phenotype it, and then they put it in your electronic medical record, and they say, ‘Well, you have high likelihood of having a mood disorder down the line in your pregnancy. Why don’t we directly refer you to a provider now so you can follow up?’ ”
Research is already underway to understand how metabolites might be linked to pregnancy outcomes, complex regional pain syndrome, and anxiety. Researchers are also investigating whether supplementing our diets with things like prebiotic fibers, apple polyphenols, or tomato paste might influence metabolites. And fecal transplants that shift the gut microbiome and metabolites could have potential in diseases like unexplained atherosclerosis, post-COVID syndrome, and hidradenitis suppurativa.
Dr. Hazen’s discovery linking TMAO with cardiovascular risk has already changed clinical practice. A blood TMAO test can help identify patients at risk who may not have traditional risk factors. “Millions have been done,” Dr. Hazen said.
Meanwhile, his drug targeting the TMAO pathway inches closer to clinical trials.
“In an animal model, we elicit improvement in heart failure, renal disease, atherosclerosis, thrombosis, aortic aneurysm, and obesity,” Dr. Hazen said. The first clinical trials will focus on renal disease.
As with any drug, the road to approval takes time. And success is not guaranteed.
But Dr. Hazen for one is optimistic.
“We are on the cusp of a new era,” Dr. Hazen said. “Like when humans first discovered insulin and glucagon were hormones that impact sugar metabolism. We now recognize myriad new ‘hormones’ in the form of gut microbiome metabolites that impact our physiology and susceptibility to diseases.”
A version of this article first appeared on Medscape.com.
Meet your new patients.
You can’t see them, but trillions — maybe quadrillions — of them travel in and out of your practice every day. They’re hungry, mysterious, community-oriented, and small. Very, very small.
They’re the microbes occupying your current patients’ guts.
Someday soon, you’ll prescribe medicine not just for humans but also for these microbes.
“I am convinced in the future our medicine cabinets are going to have not just medications like a statin for treating us, but [also] pills that treat and inhibit an enzyme in our microbes and elicit a health benefit in some chronic disease,” said Stanley Hazen, MD, PhD, co-section head of Preventive Cardiology & Rehabilitation and director of the Center for Microbiome & Human Health at Cleveland Clinic, Cleveland, Ohio.
These trillions of microbes use our food to generate substances called metabolites that can protect or harm our health, with consequences reaching far beyond our gastrointestinal tracts.
Research has linked microbial metabolites to diabetes, cardiovascular disease, liver disease, obesity, high blood pressure, neurological disorders, depression, cancer, and more. Gastroenterologist Christopher Damman, MD, a clinical associate professor at the University of Washington Medical Center, Seattle, calls it a “growing theme” in microbiome science.
Now scientists are developing treatments targeting gut microbial pathways, designed to eliminate the bad metabolites and boost the good metabolites.
One close to human therapeutic intervention is an oral treatment from Dr. Hazen’s lab targeting the metabolite trimethylamine N-oxide (TMAO), a predictor of and contributor to both cardiovascular disease and chronic kidney disease. The drug, which blocks TMAO formation, is nearing clinical trials, Dr. Hazen said.
The advantage is safety. By targeting the microbe instead of, say, an enzyme, the host (your patient) must absorb little if any drug.
Implications for the future of medicine are huge. “Gut microbial pathways contribute to diabetes, obesity, virtually everything,” Dr. Hazen said. “Therapies that target gut microbiome processes will probably even be used for psychiatric disorders within, I’ll say, 10 or 20 years.”
The Science
About 100 trillion strains of bacteria live in our guts. As humans have evolved, so have they.
Between 70% and 90% come from the phyla Firmicutes and Bacteroidetes, with person-to-person variation shaped by genetics, environment, and lifestyle.
“Everyone’s microbiome is subtly different,” said Dr. Hazen. “So the combination of what they’re making is different. All these different biologically active compounds are influencing us in subtly different ways.”
How it works: When you eat, your microbes eat, breaking down food into metabolites that interact with the thin layer of epithelial cells lining your gut. Some can be absorbed through the lining and into your bloodstream, a phenomenon known as “leaky gut.” Once in your blood, they can trigger irritation and inflammation, potentially leading to a wide variety of health issues, from gas and bloating to autoimmune conditions and mood disorders.
“On the other side of the epithelial lining, you have some of the largest concentrations of immune cells,” said Narendra Kumar, PhD, associate professor of pharmaceutical sciences at Texas A&M University, College Station, Texas.
Metabolites can influence how these immune cells work, possibly explaining why each person’s immune system behaves distinctively.
Of the 1000-plus metabolites linked to the gut microbiome, scientists have identified several that matter.
Short-chain fatty acids. When we eat fiber, colon bacteria ferment it into the beneficial short-chain fatty acids acetate, propionate, and butyrate. These bind to receptors in muscle, liver, and fat tissue, affecting the secretion of gut hormones and peptides related to appetite, inflammation, energy expenditure, and fat oxidation.
Butyrate has been linked to health benefits. It supports the integrity of the gut’s lining, stifling pathogenic gut bacteria, fighting cancer-promoting inflammation, and protecting against obesity and diabetes. It can function as a prebiotic, helping beneficial bacteria thrive. And recent studies linked an abundance of butyrate-producing bacteria with reduced bone fracture risk and hospitalization for infectious disease.
TMAO and phenylacetylglutamine. When we eat foods rich in animal proteins — think eggs, milk, fish, and especially red meat — some gut bacteria convert nutrients like choline and L-carnitine into TMAO and phenylalanine into phenylacetylglutamine. Research conducted by Dr. Hazen’s lab and replicated by others has linked both metabolites to heart problems.
In a landmark study from Dr. Hazen’s group, healthy adults who went on to develop coronary artery disease had significantly higher plasma TMAO levels than those who did not wind up with the condition. The association remained strong, even after controlling for risk factors like age, sex, smoking, high blood pressure, and high cholesterol.
In preclinical studies, elevated TMAO enhanced cardiovascular disease. TMAO-producing microbes also accentuated cardiovascular disease phenotypes in mouse models, while blocking these pathways inhibited the phenotypes.
Research suggests TMAO may harm cardiomyocytes (cells that contract and relax the heart) in dozens of ways, such as activating the expression of proteins to promote hypertrophy and fibrosis, decreasing mitochondrial function, and disrupting calcium signaling.
Another study linked phenylacetylglutamine levels to cardiac event risk in patients with heart failure. Recent mechanistic investigations suggest the metabolite alters signaling in a beta-adrenergic receptor involved in our fight-or-flight response, said Hazen.
“It’s like a rheostat on the light switch, a dimmer switch, and it’s what’s called a negative allosteric modulator,” he said. “It’s the first time that this type of behavior has ever been shown to be present for a gut microbial metabolite and a host receptor.”
Tryptophan metabolites. Microbes in your colon can convert the amino acid tryptophan, also found in animal-based foods, into neurotransmitters like serotonin and melatonin.
“The enteric nervous system, the nervous system around the gut, is immense,” said James Versalovic, MD, PhD, professor of pathology and immunology at Baylor College of Medicine, Houston. “The gut-brain axis has become a very fertile area of research.”
Lesser-known tryptophan metabolites — like indole, tryptamine, and indoleethanol — have been linked to benefits like fortifying the gut barrier, promoting the release of glucagon-like peptide 1 to reduce appetite, and protecting the liver from hepatitis. However, indole can also spur the production of indoxyl sulfate, a toxin linked to chronic kidney disease.
Bile acid byproducts. Your gut bugs also feast on (and transform) bile acids before they reabsorb and travel back to the liver.
Research is gaining traction on these secondary bile acids, which can affect inflammation and immune function in helpful and harmful ways.
One area of interest is how microbes break down hormones in bile. A recent study from Harvard showed that gut microbes convert corticoid hormones in bile into progestins, which could affect postpartum depression risk. And researchers are exploring the estrobolome — a gut microbial community dedicated to breaking down estrogen into its active form so it can be reabsorbed.
“Depending on the bacteria that you have, more or less can be recirculated back into your blood,” said Beatriz Peñalver Bernabé, PhD, an assistant professor of biomedical engineering and urology at the University of Illinois Chicago. “So you may be producing the same amount of estrogen, but depending on the bacteria you have, the real free estrogen that can bind to your cells may be very different.”
The gut microbiome can also regulate testosterone, with studies showing microbial differences in men with high testosterone vs those with less.
What Patients Can Do Now
Advances in the field of microbiome research — and the related “gut health” wellness craze — have spawned all kinds of new microbiome-based products: Like over-the-counter probiotic supplements and at-home test kits, which let you send a stool sample for analysis to reveal microbiome health and personalized diet recommendations.
But the science behind these tests is still evolving, said Dr. Damman. “The clinical inferences and applications are still pretty limited.”
For most people, the first step to fostering healthier microbial metabolites is much simpler: Diversify your diet.
“A lot of folks are missing that diversity,” Dr. Damman said.
“Eat foods and experiment with foods that you might not eat all the time,” especially fruits, vegetables, nuts, seeds, and beans.
Another strategy: Eat foods with probiotic bacteria. “I view it as an insurance policy,” said Dr. Versalovic, “fortifying my gut with probiotics, with daily yogurt, for example, at breakfast.”
Fermented foods like kimchi and kombucha can also increase microbial diversity and can even contain health-promoting postbiotics, research shows.
As for probiotic supplements, the jury’s still out.
Certain strains of probiotic bacteria may be beneficial for some patients, like those with diarrhea, Crohn’s disease, and irritable bowel syndrome, according to World Gastroenterology Organisation guidelines.
As with other interventions, individual responses can vary. A Stanford study showed that some people with metabolic syndrome improved when taking a probiotic, while others didn’t. Both groups had key differences in gut bacteria and dietary habits.
For best results, such microbiome-based interventions will need to be personalized, experts say. And the technology to do that is coming sooner than you might think.
Microbiome’s Medical Future: ‘We Are on the Cusp of a New Era’
In just a few years, artificial intelligence (AI) models could predict gut microbial composition based on data such as dietary habits and household characteristics, Dr. Kumar said.
Advancements in metabolomics and bioinformatics could soon help physicians and patients personalize their treatment approaches, said Dr. Damman.
One focus will be on fortifying the gut with whatever it lacks.
“In those individuals where certain microbes are missing, (a) how could we add them back potentially in a rational, science-driven way, and (b) maybe some of those factors that the microbes are producing out the other ends, you could give directly,” said Dr. Damman.
For example, multiple companies make butyrate as a dietary supplement, although the research is too early to support widespread use. Another option could be eating something that spurs butyrate production. One small study found that a fiber supplement formulated to increase butyrate levels in the colon reduced participants’ systolic blood pressure by an average of six points.
Another option could be synbiotics, products that combine bacteria and the food source they feed on. “If you just give a diet-based therapy, it is not going to work as much. Because what if that diet needs certain bacteria to have these beneficial metabolites?” said Ashutosh Mangalam, PhD, associate professor of pathology at the University of Iowa Carver College of Medicine, Iowa City.
Dr. Mangalam studies links between bacterial metabolism of phytoestrogens in soy foods and multiple sclerosis (MS) development. He is using AI to understand differences in metabolites in patients with MS vs healthy controls to determine how to target them.
Gut microbial metabolites could also affect disease screening and intervention. What if gut microbe sequencing could predict a pregnant person’s risk of developing depression, something now assessed through simple questionnaires?
“Imagine that your doctor says, ‘Okay, give me a poop sample,’ ” Dr. Bernabé said. “Then they phenotype it, and then they put it in your electronic medical record, and they say, ‘Well, you have high likelihood of having a mood disorder down the line in your pregnancy. Why don’t we directly refer you to a provider now so you can follow up?’ ”
Research is already underway to understand how metabolites might be linked to pregnancy outcomes, complex regional pain syndrome, and anxiety. Researchers are also investigating whether supplementing our diets with things like prebiotic fibers, apple polyphenols, or tomato paste might influence metabolites. And fecal transplants that shift the gut microbiome and metabolites could have potential in diseases like unexplained atherosclerosis, post-COVID syndrome, and hidradenitis suppurativa.
Dr. Hazen’s discovery linking TMAO with cardiovascular risk has already changed clinical practice. A blood TMAO test can help identify patients at risk who may not have traditional risk factors. “Millions have been done,” Dr. Hazen said.
Meanwhile, his drug targeting the TMAO pathway inches closer to clinical trials.
“In an animal model, we elicit improvement in heart failure, renal disease, atherosclerosis, thrombosis, aortic aneurysm, and obesity,” Dr. Hazen said. The first clinical trials will focus on renal disease.
As with any drug, the road to approval takes time. And success is not guaranteed.
But Dr. Hazen for one is optimistic.
“We are on the cusp of a new era,” Dr. Hazen said. “Like when humans first discovered insulin and glucagon were hormones that impact sugar metabolism. We now recognize myriad new ‘hormones’ in the form of gut microbiome metabolites that impact our physiology and susceptibility to diseases.”
A version of this article first appeared on Medscape.com.
Over One Third of Patients Develop Exocrine Pancreatic Insufficiency After Acute Pancreatitis
TOPLINE:
Over one third of patients with acute pancreatitis develop exocrine pancreatic insufficiency (EPI) at 12 months, with the key predictors being idiopathic etiology, moderately severe or severe disease, and preexisting diabetes.
METHODOLOGY:
- EPI has traditionally been associated with chronic pancreatitis, but its prevalence and natural history following acute pancreatitis are less well defined.
- Researchers conducted a prospective cohort study including 85 hospital inpatients (mean age, 54.7 years; 48.2% women) diagnosed with acute pancreatitis from three tertiary institutions in the United States.
- Severity of acute pancreatitis was classified according to the Revised Atlanta Criteria.
- EPI was assessed by measuring fecal elastase 1 (FE-1) levels from stool samples at baseline and at 3 and 12 months after enrollment. EPI was defined by FE-1 levels ≤ 200 μg/g stool, with mild and severe EPI categorized by FE-1 levels of 101-200 μg/g stool and ≤ 100 μg/g stool, respectively.
- The prevalence of EPI was assessed at 3 and 12 months after acute pancreatitis. The study also identified the predictors of EPI, including the role of etiology and severity of acute pancreatitis and preexisting diabetes.
TAKEAWAY:
- EPI was present in 34.1% participants at 12 months after an acute pancreatitis attack, with 22.4% having severe EPI.
- Even 12.8% of those with an index mild attack of acute pancreatitis had severe EPI at 12 months.
- The odds of developing EPI at 12 months increased fourfold with idiopathic etiology of acute pancreatitis (P = .0094).
- The odds of developing EPI increased over threefold with moderately severe or severe acute pancreatitis (P = .025) and preexisting diabetes (P = .031).
- The prevalence of severe EPI after acute pancreatitis decreased from 29% at baseline to 26% at 3 months and 22% at 12 months.
IN PRACTICE:
“While specific subpopulations may have identified clinical risk factors, it will remain important to have a low threshold for testing and treatment as there remains much to learn about mechanisms leading to EPI after [acute pancreatitis],” the authors wrote.
SOURCE:
This study, led by Anna Evans Phillips, MD, MS, University of Pittsburgh School of Medicine in Pennsylvania, was published online in eClinicalMedicine.
LIMITATIONS:
Participants were often transferred from other hospitals with differing management techniques, which may have introduced selection bias. The use of FE-1 levels may have had diagnostic limitations. The study did not assess the impact of pancreatic enzyme replacement therapy on recovery from EPI. Some patients with early chronic pancreatitis may have been included owing to the lack of diagnostic clarity.
DISCLOSURES:
The study was supported by an investigator-initiated research grant from AbbVie. Some authors received funding for research from AbbVie. One of the authors declared serving as a consultant and scientific advisory board member and being an equity holder in biotechnology, biopharmaceutical, and diagnostics companies. Another author declared support from the Cystic Fibrosis Foundation and the American Society for Parenteral and Enteral Nutrition.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
TOPLINE:
Over one third of patients with acute pancreatitis develop exocrine pancreatic insufficiency (EPI) at 12 months, with the key predictors being idiopathic etiology, moderately severe or severe disease, and preexisting diabetes.
METHODOLOGY:
- EPI has traditionally been associated with chronic pancreatitis, but its prevalence and natural history following acute pancreatitis are less well defined.
- Researchers conducted a prospective cohort study including 85 hospital inpatients (mean age, 54.7 years; 48.2% women) diagnosed with acute pancreatitis from three tertiary institutions in the United States.
- Severity of acute pancreatitis was classified according to the Revised Atlanta Criteria.
- EPI was assessed by measuring fecal elastase 1 (FE-1) levels from stool samples at baseline and at 3 and 12 months after enrollment. EPI was defined by FE-1 levels ≤ 200 μg/g stool, with mild and severe EPI categorized by FE-1 levels of 101-200 μg/g stool and ≤ 100 μg/g stool, respectively.
- The prevalence of EPI was assessed at 3 and 12 months after acute pancreatitis. The study also identified the predictors of EPI, including the role of etiology and severity of acute pancreatitis and preexisting diabetes.
TAKEAWAY:
- EPI was present in 34.1% participants at 12 months after an acute pancreatitis attack, with 22.4% having severe EPI.
- Even 12.8% of those with an index mild attack of acute pancreatitis had severe EPI at 12 months.
- The odds of developing EPI at 12 months increased fourfold with idiopathic etiology of acute pancreatitis (P = .0094).
- The odds of developing EPI increased over threefold with moderately severe or severe acute pancreatitis (P = .025) and preexisting diabetes (P = .031).
- The prevalence of severe EPI after acute pancreatitis decreased from 29% at baseline to 26% at 3 months and 22% at 12 months.
IN PRACTICE:
“While specific subpopulations may have identified clinical risk factors, it will remain important to have a low threshold for testing and treatment as there remains much to learn about mechanisms leading to EPI after [acute pancreatitis],” the authors wrote.
SOURCE:
This study, led by Anna Evans Phillips, MD, MS, University of Pittsburgh School of Medicine in Pennsylvania, was published online in eClinicalMedicine.
LIMITATIONS:
Participants were often transferred from other hospitals with differing management techniques, which may have introduced selection bias. The use of FE-1 levels may have had diagnostic limitations. The study did not assess the impact of pancreatic enzyme replacement therapy on recovery from EPI. Some patients with early chronic pancreatitis may have been included owing to the lack of diagnostic clarity.
DISCLOSURES:
The study was supported by an investigator-initiated research grant from AbbVie. Some authors received funding for research from AbbVie. One of the authors declared serving as a consultant and scientific advisory board member and being an equity holder in biotechnology, biopharmaceutical, and diagnostics companies. Another author declared support from the Cystic Fibrosis Foundation and the American Society for Parenteral and Enteral Nutrition.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
TOPLINE:
Over one third of patients with acute pancreatitis develop exocrine pancreatic insufficiency (EPI) at 12 months, with the key predictors being idiopathic etiology, moderately severe or severe disease, and preexisting diabetes.
METHODOLOGY:
- EPI has traditionally been associated with chronic pancreatitis, but its prevalence and natural history following acute pancreatitis are less well defined.
- Researchers conducted a prospective cohort study including 85 hospital inpatients (mean age, 54.7 years; 48.2% women) diagnosed with acute pancreatitis from three tertiary institutions in the United States.
- Severity of acute pancreatitis was classified according to the Revised Atlanta Criteria.
- EPI was assessed by measuring fecal elastase 1 (FE-1) levels from stool samples at baseline and at 3 and 12 months after enrollment. EPI was defined by FE-1 levels ≤ 200 μg/g stool, with mild and severe EPI categorized by FE-1 levels of 101-200 μg/g stool and ≤ 100 μg/g stool, respectively.
- The prevalence of EPI was assessed at 3 and 12 months after acute pancreatitis. The study also identified the predictors of EPI, including the role of etiology and severity of acute pancreatitis and preexisting diabetes.
TAKEAWAY:
- EPI was present in 34.1% participants at 12 months after an acute pancreatitis attack, with 22.4% having severe EPI.
- Even 12.8% of those with an index mild attack of acute pancreatitis had severe EPI at 12 months.
- The odds of developing EPI at 12 months increased fourfold with idiopathic etiology of acute pancreatitis (P = .0094).
- The odds of developing EPI increased over threefold with moderately severe or severe acute pancreatitis (P = .025) and preexisting diabetes (P = .031).
- The prevalence of severe EPI after acute pancreatitis decreased from 29% at baseline to 26% at 3 months and 22% at 12 months.
IN PRACTICE:
“While specific subpopulations may have identified clinical risk factors, it will remain important to have a low threshold for testing and treatment as there remains much to learn about mechanisms leading to EPI after [acute pancreatitis],” the authors wrote.
SOURCE:
This study, led by Anna Evans Phillips, MD, MS, University of Pittsburgh School of Medicine in Pennsylvania, was published online in eClinicalMedicine.
LIMITATIONS:
Participants were often transferred from other hospitals with differing management techniques, which may have introduced selection bias. The use of FE-1 levels may have had diagnostic limitations. The study did not assess the impact of pancreatic enzyme replacement therapy on recovery from EPI. Some patients with early chronic pancreatitis may have been included owing to the lack of diagnostic clarity.
DISCLOSURES:
The study was supported by an investigator-initiated research grant from AbbVie. Some authors received funding for research from AbbVie. One of the authors declared serving as a consultant and scientific advisory board member and being an equity holder in biotechnology, biopharmaceutical, and diagnostics companies. Another author declared support from the Cystic Fibrosis Foundation and the American Society for Parenteral and Enteral Nutrition.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.
The Next Frontier of Antibiotic Discovery: Inside Your Gut
Scientists at Stanford University and the University of Pennsylvania have discovered a new antibiotic candidate in a surprising place: the human gut.
In mice, the antibiotic — a peptide known as prevotellin-2 — showed antimicrobial potency on par with polymyxin B, an antibiotic medication used to treat multidrug-resistant infections. Meanwhile, the peptide mainly left commensal, or beneficial, bacteria alone. The study, published in Cell, also identified several other potent antibiotic peptides with the potential to combat antimicrobial-resistant infections.
The research is part of a larger quest to find new antibiotics that can fight drug-resistant infections, a critical public health threat with more than 2.8 million cases and 35,000 deaths annually in the United States. That quest is urgent, said study author César de la Fuente, PhD, professor of bioengineering at the University of Pennsylvania, Philadelphia.
“The main pillars that have enabled us to almost double our lifespan in the last 100 years or so have been antibiotics, vaccines, and clean water,” said Dr. de la Fuente. “Imagine taking out one of those. I think it would be pretty dramatic.” (Dr. De la Fuente’s lab has become known for finding antibiotic candidates in unusual places, like ancient genetic information of Neanderthals and woolly mammoths.)
The first widely used antibiotic, penicillin, was discovered in 1928, when a physician studying Staphylococcus bacteria returned to his lab after summer break to find mold growing in one of his petri dishes. But many other antibiotics — like streptomycin, tetracycline, and erythromycin — were discovered from soil bacteria, which produce variations of these substances to compete with other microorganisms.
By looking in the gut microbiome, the researchers hoped to identify peptides that the trillions of microbes use against each other in the fight for limited resources — ideally, peptides that wouldn’t broadly kill off the entire microbiome.
Kill the Bad, Spare the Good
Many traditional antibiotics are small molecules. This means they can wipe out the good bacteria in your body, and because each targets a specific bacterial function, bad bacteria can become resistant to them.
Peptide antibiotics, on the other hand, don’t diffuse into the whole body. If taken orally, they stay in the gut; if taken intravenously, they generally stay in the blood. And because of how they kill bacteria, targeting the membrane, they’re also less prone to bacterial resistance.
The microbiome is like a big reservoir of pathogens, said Ami Bhatt, MD, PhD, hematologist at Stanford University in California and one of the study’s authors. Because many antibiotics kill healthy gut bacteria, “what you have left over,” Dr. Bhatt said, “is this big open niche that gets filled up with multidrug-resistant organisms like E coli [Escherichia coli] or vancomycin-resistant Enterococcus.”
Dr. Bhatt has seen cancer patients undergo successful treatment only to die of a multidrug-resistant infection, because current antibiotics fail against those pathogens. “That’s like winning the battle to lose the war.”
By investigating the microbiome, “we wanted to see if we could identify antimicrobial peptides that might spare key members of our regular microbiome, so that we wouldn’t totally disrupt the microbiome the way we do when we use broad-spectrum, small molecule–based antibiotics,” Dr. Bhatt said.
The researchers used artificial intelligence to sift through 400,000 proteins to predict, based on known antibiotics, which peptide sequences might have antimicrobial properties. From the results, they chose 78 peptides to synthesize and test.
“The application of computational approaches combined with experimental validation is very powerful and exciting,” said Jennifer Geddes-McAlister, PhD, professor of cell biology at the University of Guelph in Ontario, Canada, who was not involved in the study. “The study is robust in its approach to microbiome sampling.”
The Long Journey from Lab to Clinic
More than half of the peptides the team tested effectively inhibited the growth of harmful bacteria, and prevotellin-2 (derived from the bacteria Prevotella copri)stood out as the most powerful.
“The study validates experimental data from the lab using animal models, which moves discoveries closer to the clinic,” said Dr. Geddes-McAlister. “Further testing with clinical trials is needed, but the potential for clinical application is promising.”
Unfortunately, that’s not likely to happen anytime soon, said Dr. de la Fuente. “There is not enough economic incentive” for companies to develop new antibiotics. Ten years is his most hopeful guess for when we might see prevotellin-2, or a similar antibiotic, complete clinical trials.
A version of this article first appeared on Medscape.com.
Scientists at Stanford University and the University of Pennsylvania have discovered a new antibiotic candidate in a surprising place: the human gut.
In mice, the antibiotic — a peptide known as prevotellin-2 — showed antimicrobial potency on par with polymyxin B, an antibiotic medication used to treat multidrug-resistant infections. Meanwhile, the peptide mainly left commensal, or beneficial, bacteria alone. The study, published in Cell, also identified several other potent antibiotic peptides with the potential to combat antimicrobial-resistant infections.
The research is part of a larger quest to find new antibiotics that can fight drug-resistant infections, a critical public health threat with more than 2.8 million cases and 35,000 deaths annually in the United States. That quest is urgent, said study author César de la Fuente, PhD, professor of bioengineering at the University of Pennsylvania, Philadelphia.
“The main pillars that have enabled us to almost double our lifespan in the last 100 years or so have been antibiotics, vaccines, and clean water,” said Dr. de la Fuente. “Imagine taking out one of those. I think it would be pretty dramatic.” (Dr. De la Fuente’s lab has become known for finding antibiotic candidates in unusual places, like ancient genetic information of Neanderthals and woolly mammoths.)
The first widely used antibiotic, penicillin, was discovered in 1928, when a physician studying Staphylococcus bacteria returned to his lab after summer break to find mold growing in one of his petri dishes. But many other antibiotics — like streptomycin, tetracycline, and erythromycin — were discovered from soil bacteria, which produce variations of these substances to compete with other microorganisms.
By looking in the gut microbiome, the researchers hoped to identify peptides that the trillions of microbes use against each other in the fight for limited resources — ideally, peptides that wouldn’t broadly kill off the entire microbiome.
Kill the Bad, Spare the Good
Many traditional antibiotics are small molecules. This means they can wipe out the good bacteria in your body, and because each targets a specific bacterial function, bad bacteria can become resistant to them.
Peptide antibiotics, on the other hand, don’t diffuse into the whole body. If taken orally, they stay in the gut; if taken intravenously, they generally stay in the blood. And because of how they kill bacteria, targeting the membrane, they’re also less prone to bacterial resistance.
The microbiome is like a big reservoir of pathogens, said Ami Bhatt, MD, PhD, hematologist at Stanford University in California and one of the study’s authors. Because many antibiotics kill healthy gut bacteria, “what you have left over,” Dr. Bhatt said, “is this big open niche that gets filled up with multidrug-resistant organisms like E coli [Escherichia coli] or vancomycin-resistant Enterococcus.”
Dr. Bhatt has seen cancer patients undergo successful treatment only to die of a multidrug-resistant infection, because current antibiotics fail against those pathogens. “That’s like winning the battle to lose the war.”
By investigating the microbiome, “we wanted to see if we could identify antimicrobial peptides that might spare key members of our regular microbiome, so that we wouldn’t totally disrupt the microbiome the way we do when we use broad-spectrum, small molecule–based antibiotics,” Dr. Bhatt said.
The researchers used artificial intelligence to sift through 400,000 proteins to predict, based on known antibiotics, which peptide sequences might have antimicrobial properties. From the results, they chose 78 peptides to synthesize and test.
“The application of computational approaches combined with experimental validation is very powerful and exciting,” said Jennifer Geddes-McAlister, PhD, professor of cell biology at the University of Guelph in Ontario, Canada, who was not involved in the study. “The study is robust in its approach to microbiome sampling.”
The Long Journey from Lab to Clinic
More than half of the peptides the team tested effectively inhibited the growth of harmful bacteria, and prevotellin-2 (derived from the bacteria Prevotella copri)stood out as the most powerful.
“The study validates experimental data from the lab using animal models, which moves discoveries closer to the clinic,” said Dr. Geddes-McAlister. “Further testing with clinical trials is needed, but the potential for clinical application is promising.”
Unfortunately, that’s not likely to happen anytime soon, said Dr. de la Fuente. “There is not enough economic incentive” for companies to develop new antibiotics. Ten years is his most hopeful guess for when we might see prevotellin-2, or a similar antibiotic, complete clinical trials.
A version of this article first appeared on Medscape.com.
Scientists at Stanford University and the University of Pennsylvania have discovered a new antibiotic candidate in a surprising place: the human gut.
In mice, the antibiotic — a peptide known as prevotellin-2 — showed antimicrobial potency on par with polymyxin B, an antibiotic medication used to treat multidrug-resistant infections. Meanwhile, the peptide mainly left commensal, or beneficial, bacteria alone. The study, published in Cell, also identified several other potent antibiotic peptides with the potential to combat antimicrobial-resistant infections.
The research is part of a larger quest to find new antibiotics that can fight drug-resistant infections, a critical public health threat with more than 2.8 million cases and 35,000 deaths annually in the United States. That quest is urgent, said study author César de la Fuente, PhD, professor of bioengineering at the University of Pennsylvania, Philadelphia.
“The main pillars that have enabled us to almost double our lifespan in the last 100 years or so have been antibiotics, vaccines, and clean water,” said Dr. de la Fuente. “Imagine taking out one of those. I think it would be pretty dramatic.” (Dr. De la Fuente’s lab has become known for finding antibiotic candidates in unusual places, like ancient genetic information of Neanderthals and woolly mammoths.)
The first widely used antibiotic, penicillin, was discovered in 1928, when a physician studying Staphylococcus bacteria returned to his lab after summer break to find mold growing in one of his petri dishes. But many other antibiotics — like streptomycin, tetracycline, and erythromycin — were discovered from soil bacteria, which produce variations of these substances to compete with other microorganisms.
By looking in the gut microbiome, the researchers hoped to identify peptides that the trillions of microbes use against each other in the fight for limited resources — ideally, peptides that wouldn’t broadly kill off the entire microbiome.
Kill the Bad, Spare the Good
Many traditional antibiotics are small molecules. This means they can wipe out the good bacteria in your body, and because each targets a specific bacterial function, bad bacteria can become resistant to them.
Peptide antibiotics, on the other hand, don’t diffuse into the whole body. If taken orally, they stay in the gut; if taken intravenously, they generally stay in the blood. And because of how they kill bacteria, targeting the membrane, they’re also less prone to bacterial resistance.
The microbiome is like a big reservoir of pathogens, said Ami Bhatt, MD, PhD, hematologist at Stanford University in California and one of the study’s authors. Because many antibiotics kill healthy gut bacteria, “what you have left over,” Dr. Bhatt said, “is this big open niche that gets filled up with multidrug-resistant organisms like E coli [Escherichia coli] or vancomycin-resistant Enterococcus.”
Dr. Bhatt has seen cancer patients undergo successful treatment only to die of a multidrug-resistant infection, because current antibiotics fail against those pathogens. “That’s like winning the battle to lose the war.”
By investigating the microbiome, “we wanted to see if we could identify antimicrobial peptides that might spare key members of our regular microbiome, so that we wouldn’t totally disrupt the microbiome the way we do when we use broad-spectrum, small molecule–based antibiotics,” Dr. Bhatt said.
The researchers used artificial intelligence to sift through 400,000 proteins to predict, based on known antibiotics, which peptide sequences might have antimicrobial properties. From the results, they chose 78 peptides to synthesize and test.
“The application of computational approaches combined with experimental validation is very powerful and exciting,” said Jennifer Geddes-McAlister, PhD, professor of cell biology at the University of Guelph in Ontario, Canada, who was not involved in the study. “The study is robust in its approach to microbiome sampling.”
The Long Journey from Lab to Clinic
More than half of the peptides the team tested effectively inhibited the growth of harmful bacteria, and prevotellin-2 (derived from the bacteria Prevotella copri)stood out as the most powerful.
“The study validates experimental data from the lab using animal models, which moves discoveries closer to the clinic,” said Dr. Geddes-McAlister. “Further testing with clinical trials is needed, but the potential for clinical application is promising.”
Unfortunately, that’s not likely to happen anytime soon, said Dr. de la Fuente. “There is not enough economic incentive” for companies to develop new antibiotics. Ten years is his most hopeful guess for when we might see prevotellin-2, or a similar antibiotic, complete clinical trials.
A version of this article first appeared on Medscape.com.
FROM CELL