If the microbiome of those eating plant-based diets protects against the toxic effects of TMAO, what about swapping gut flora?
Can Vegan Fecal Transplants Lower TMAO Levels?
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Almost 2,500 years ago, Hippocrates stated that “All disease begins in the gut.” Feed our gut bacteria right, with whole plant foods, and they feed us right back, with beneficial compounds like butyrate, which gut bugs make from fiber. Feed them wrong, on the other hand, and they can produce detrimental compounds, like TMAO, which our gut bugs make from cheese, seafood, eggs, and meat.
Now we used to think that TMAO only contributed to cardiovascular diseases, like heart disease and stroke. But more recently, it has been linked with everything from psoriatic arthritis to polycystic ovary syndrome. But I’m most concerned about our leading killers, though. If you look at the top ten causes of death in the United States, we know about heart disease and stroke, killers #1 and #5, but recently, an association has been found between blood levels of TMAO and the risks of various cancers, killer #2. It could be the inflammation caused by TMAO that explains the link between TMAO and cancer, but it could also be oxidative stress (free radicals), DNA damage, or a disruption in protein folding.
Killer #4 are chronic obstructive pulmonary diseases like emphysema, and TMAO is associated with premature death in patients with exacerbated chronic obstructive pulmonary disease––though they suspect it’s just due to them dying from more cardiovascular disease.
The link to stroke is a no-brainer—no pun intended—because of the higher blood pressure associated with higher TMAO levels, as well as the greater likelihood of clot formation in those with atrial fibrillation. And those with higher TMAO levels also appear to have worse strokes, and four times the odds of death.
Killer #6 is Alzheimer’s disease. Does TMAO even get up into the brain? Yes, TMAO is present in human cerebrospinal fluid, which bathes the brain, and indeed, the levels are higher in both those with mild cognitive dysfunction and those with Alzheimer’s disease dementia. In the brain, TMAO has been shown to induce neuronal senescence (meaning deterioration with age), increased oxidative stress, and impaired mitochondrial function––all of which may contribute to brain aging and cognitive impairment.
Killer #7 is diabetes, and people with higher TMAO levels are approximately 50 percent more likely to have diabetes, too. Killer #8 is pneumonia, and TMAO predicts fatal outcomes in pneumonia patients, even without evident heart disease. Killer #9 is kidney disease, and TMAO is strongly related to kidney function, and predicts fatal outcomes there as well. Over a period of five years, more than half of chronic kidney disease patients who started out with average or higher TMAO levels were dead, whereas among those in the lowest third of levels, nearly 90 percent remained alive.
Okay, so how can we lower the TMAO levels in our blood? Because TMAO originates from dietary sources, we could limit our intake of choline and carnitine-rich foods. But they’re so widespread. We’re talkin’ meat, eggs, and dairy. Therefore, restriction of foods rich in TMAO-creating nutrients may not be practical. I mean, can’t we just get a vegan fecal transplant? Vegan donors were kind enough to provide the investigators with a fresh morning sample.
If you remember, if you give a vegan a steak, despite all that carnitine, they make almost no TMAO compared to a meat-eater, presumably because they haven’t been fostering steak-eating bugs in their gut.
Remarkably, even if you give plant-based eaters the equivalent of a 20-ounce steak every day for two months, only about half start ramping up production, showing just how far their gut flora had to change. The capacity of veggie feces to churn out TMAO is almost nonexistent. So, instead of eating healthier, why not just get some of that sweet vegan poop off the brown market.
In a double-blind, randomized, controlled trial, research subjects either got vegan poop or their own poop back. The complete stool production was stirred—not shaken—and then infused through a hose down their nose, and. . .it didn’t work.
First of all, the vegans they recruited for their study started out making TMAO themselves, as opposed to the other study where they didn’t make any at all. This may be because the other study required the vegans to have been vegan for at least a year, and this study didn’t. So yeah, not much of a change in TMAO running through their bodies two weeks after getting the vegan poop, but the vegan poop they got seemed to start out with some capacity to produce TMAO in the first place.
So, the failure to improve after the vegan fecal transplant could be related to limited baseline microbiome differences, as well as the continuation of an omnivorous diet after the transplant. What’s the point of trying to reset your microbiome if you’re just going to eat meat? Well, the researchers didn’t want to switch people to a plant-based diet, since they knew that alone can change your microbiome, and they didn’t want to introduce any extra factors. Bottom line—no pun intended—it looks like there may not be any shortcuts. We may just have to eat a healthier diet.
Please consider volunteering to help out on the site.
- Sieck GC. Physiology in Perspective: The Body's Tubes Sustain Life but Underlie Disease. Physiology (Bethesda). 2016;31(5):314-5.
- Sonnenburg JL, Bäckhed F. Diet-microbiota interactions as moderators of human metabolism. Nature. 2016;535(7610):56-64.
- He Z, Chen ZY. What Are Missing Parts in the Research Story of Trimethylamine-N-oxide (TMAO)?. J Agric Food Chem. 2017;65(26):5227-8.
- Coras R, Kavanaugh A, Boyd T, et al. Choline metabolite, trimethylamine N-oxide (TMAO), is associated with inflammation in psoriatic arthritis. Clin Exp Rheumatol. 2019;37(3):481-4.
- Eyupoglu ND, Caliskan Guzelce E, Acikgoz A, et al. Circulating gut microbiota metabolite trimethylamine N-oxide and oral contraceptive use in polycystic ovary syndrome. Clin Endocrinol (Oxf). 2019;91(6):810-5.
- Heron M. Deaths: Leading Causes for 2017. Natl Vital Stat Rep. 2019;68(6):1-77.
- Chan CWH, Law BMH, Waye MMY, Chan JYW, So WKW, Chow KM. Trimethylamine-N-oxide as One Hypothetical Link for the Relationship between Intestinal Microbiota and Cancer - Where We Are and Where Shall We Go?. J Cancer. 2019;10(23):5874-82.
- Ottiger M, Nickler M, Steuer C, et al. Gut, microbiota-dependent trimethylamine-N-oxide is associated with long-term all-cause mortality in patients with exacerbated chronic obstructive pulmonary disease. Nutrition. 2018;45:135-41.e1.
- Rexidamu M, Li H, Jin H, Huang J. Serum levels of Trimethylamine-N-oxide in patients with ischemic stroke. Biosci Rep. 2019;39(6):BSR20190515.
- Ge X, Zheng L, Zhuang R, et al. The Gut Microbial Metabolite Trimethylamine N-Oxide and Hypertension Risk: A Systematic Review and Dose-Response Meta-analysis. Adv Nutr. 2020;11(1):66-76.
- Gong D, Zhang L, Zhang Y, Wang F, Zhao Z, Zhou X. Gut Microbial Metabolite Trimethylamine N-Oxide Is Related to Thrombus Formation in Atrial Fibrillation Patients. Am J Med Sci. 2019;358(6):422-8.
- Zhai Q, Wang X, Chen C, et al. Prognostic Value of Plasma Trimethylamine N-Oxide Levels in Patients with Acute Ischemic Stroke. Cell Mol Neurobiol. 2019;39(8):1201-6.
- Del Rio D, Zimetti F, Caffarra P, et al. The Gut Microbial Metabolite Trimethylamine-N-Oxide Is Present in Human Cerebrospinal Fluid. Nutrients. 2017;9(10):1053.
- Vogt NM, Romano KA, Darst BF, et al. The gut microbiota-derived metabolite trimethylamine N-oxide is elevated in Alzheimer's disease. Alzheimers Res Ther. 2018;10(1):124.
- Zhuang R, Ge X, Han L, et al. Gut microbe-generated metabolite trimethylamine N-oxide and the risk of diabetes: A systematic review and dose-response meta-analysis. Obes Rev. 2019;20(6):883-94.
- Ottiger M, Nickler M, Steuer C, et al. Trimethylamine-N-oxide (TMAO) predicts fatal outcomes in community-acquired pneumonia patients without evident coronary artery disease. Eur J Intern Med. 2016;36:67-73.
- Missailidis C, Hällqvist J, Qureshi AR, et al. Serum Trimethylamine-N-Oxide Is Strongly Related to Renal Function and Predicts Outcome in Chronic Kidney Disease. PLoS One. 2016;11(1):e0141738.
- Smits LP, Kootte RS, Levin E, et al. Effect of Vegan Fecal Microbiota Transplantation on Carnitine- and Choline-Derived Trimethylamine-N-Oxide Production and Vascular Inflammation in Patients With Metabolic Syndrome. J Am Heart Assoc. 2018;7(7):e008342.
- Koeth RA, Wang Z, Levison BS, et al. Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med. 2013;19(5):576-85.
- Koeth RA, Lam-Galvez BR, Kirsop J, et al. l-Carnitine in omnivorous diets induces an atherogenic gut microbial pathway in humans. J Clin Invest. 2019;129(1):373-87.
Video production by Glass Entertainment
Motion graphics by Avo Media
- Alzheimer’s disease
- animal products
- arthritis
- brain health
- butyrate
- cardiovascular disease
- carnitine
- cheese
- choline
- cognition
- COPD
- dairy
- dementia
- diabetes
- DNA damage
- eggs
- fecal transplant
- fiber
- gut flora
- heart disease
- kidney disease
- kidney function
- meat
- microbiome
- oxidative stress
- PCOS
- Plant-Based Diets
- pneumonia
- seafood
- stroke
- TMAO
- vegans
- vegetarians
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Almost 2,500 years ago, Hippocrates stated that “All disease begins in the gut.” Feed our gut bacteria right, with whole plant foods, and they feed us right back, with beneficial compounds like butyrate, which gut bugs make from fiber. Feed them wrong, on the other hand, and they can produce detrimental compounds, like TMAO, which our gut bugs make from cheese, seafood, eggs, and meat.
Now we used to think that TMAO only contributed to cardiovascular diseases, like heart disease and stroke. But more recently, it has been linked with everything from psoriatic arthritis to polycystic ovary syndrome. But I’m most concerned about our leading killers, though. If you look at the top ten causes of death in the United States, we know about heart disease and stroke, killers #1 and #5, but recently, an association has been found between blood levels of TMAO and the risks of various cancers, killer #2. It could be the inflammation caused by TMAO that explains the link between TMAO and cancer, but it could also be oxidative stress (free radicals), DNA damage, or a disruption in protein folding.
Killer #4 are chronic obstructive pulmonary diseases like emphysema, and TMAO is associated with premature death in patients with exacerbated chronic obstructive pulmonary disease––though they suspect it’s just due to them dying from more cardiovascular disease.
The link to stroke is a no-brainer—no pun intended—because of the higher blood pressure associated with higher TMAO levels, as well as the greater likelihood of clot formation in those with atrial fibrillation. And those with higher TMAO levels also appear to have worse strokes, and four times the odds of death.
Killer #6 is Alzheimer’s disease. Does TMAO even get up into the brain? Yes, TMAO is present in human cerebrospinal fluid, which bathes the brain, and indeed, the levels are higher in both those with mild cognitive dysfunction and those with Alzheimer’s disease dementia. In the brain, TMAO has been shown to induce neuronal senescence (meaning deterioration with age), increased oxidative stress, and impaired mitochondrial function––all of which may contribute to brain aging and cognitive impairment.
Killer #7 is diabetes, and people with higher TMAO levels are approximately 50 percent more likely to have diabetes, too. Killer #8 is pneumonia, and TMAO predicts fatal outcomes in pneumonia patients, even without evident heart disease. Killer #9 is kidney disease, and TMAO is strongly related to kidney function, and predicts fatal outcomes there as well. Over a period of five years, more than half of chronic kidney disease patients who started out with average or higher TMAO levels were dead, whereas among those in the lowest third of levels, nearly 90 percent remained alive.
Okay, so how can we lower the TMAO levels in our blood? Because TMAO originates from dietary sources, we could limit our intake of choline and carnitine-rich foods. But they’re so widespread. We’re talkin’ meat, eggs, and dairy. Therefore, restriction of foods rich in TMAO-creating nutrients may not be practical. I mean, can’t we just get a vegan fecal transplant? Vegan donors were kind enough to provide the investigators with a fresh morning sample.
If you remember, if you give a vegan a steak, despite all that carnitine, they make almost no TMAO compared to a meat-eater, presumably because they haven’t been fostering steak-eating bugs in their gut.
Remarkably, even if you give plant-based eaters the equivalent of a 20-ounce steak every day for two months, only about half start ramping up production, showing just how far their gut flora had to change. The capacity of veggie feces to churn out TMAO is almost nonexistent. So, instead of eating healthier, why not just get some of that sweet vegan poop off the brown market.
In a double-blind, randomized, controlled trial, research subjects either got vegan poop or their own poop back. The complete stool production was stirred—not shaken—and then infused through a hose down their nose, and. . .it didn’t work.
First of all, the vegans they recruited for their study started out making TMAO themselves, as opposed to the other study where they didn’t make any at all. This may be because the other study required the vegans to have been vegan for at least a year, and this study didn’t. So yeah, not much of a change in TMAO running through their bodies two weeks after getting the vegan poop, but the vegan poop they got seemed to start out with some capacity to produce TMAO in the first place.
So, the failure to improve after the vegan fecal transplant could be related to limited baseline microbiome differences, as well as the continuation of an omnivorous diet after the transplant. What’s the point of trying to reset your microbiome if you’re just going to eat meat? Well, the researchers didn’t want to switch people to a plant-based diet, since they knew that alone can change your microbiome, and they didn’t want to introduce any extra factors. Bottom line—no pun intended—it looks like there may not be any shortcuts. We may just have to eat a healthier diet.
Please consider volunteering to help out on the site.
- Sieck GC. Physiology in Perspective: The Body's Tubes Sustain Life but Underlie Disease. Physiology (Bethesda). 2016;31(5):314-5.
- Sonnenburg JL, Bäckhed F. Diet-microbiota interactions as moderators of human metabolism. Nature. 2016;535(7610):56-64.
- He Z, Chen ZY. What Are Missing Parts in the Research Story of Trimethylamine-N-oxide (TMAO)?. J Agric Food Chem. 2017;65(26):5227-8.
- Coras R, Kavanaugh A, Boyd T, et al. Choline metabolite, trimethylamine N-oxide (TMAO), is associated with inflammation in psoriatic arthritis. Clin Exp Rheumatol. 2019;37(3):481-4.
- Eyupoglu ND, Caliskan Guzelce E, Acikgoz A, et al. Circulating gut microbiota metabolite trimethylamine N-oxide and oral contraceptive use in polycystic ovary syndrome. Clin Endocrinol (Oxf). 2019;91(6):810-5.
- Heron M. Deaths: Leading Causes for 2017. Natl Vital Stat Rep. 2019;68(6):1-77.
- Chan CWH, Law BMH, Waye MMY, Chan JYW, So WKW, Chow KM. Trimethylamine-N-oxide as One Hypothetical Link for the Relationship between Intestinal Microbiota and Cancer - Where We Are and Where Shall We Go?. J Cancer. 2019;10(23):5874-82.
- Ottiger M, Nickler M, Steuer C, et al. Gut, microbiota-dependent trimethylamine-N-oxide is associated with long-term all-cause mortality in patients with exacerbated chronic obstructive pulmonary disease. Nutrition. 2018;45:135-41.e1.
- Rexidamu M, Li H, Jin H, Huang J. Serum levels of Trimethylamine-N-oxide in patients with ischemic stroke. Biosci Rep. 2019;39(6):BSR20190515.
- Ge X, Zheng L, Zhuang R, et al. The Gut Microbial Metabolite Trimethylamine N-Oxide and Hypertension Risk: A Systematic Review and Dose-Response Meta-analysis. Adv Nutr. 2020;11(1):66-76.
- Gong D, Zhang L, Zhang Y, Wang F, Zhao Z, Zhou X. Gut Microbial Metabolite Trimethylamine N-Oxide Is Related to Thrombus Formation in Atrial Fibrillation Patients. Am J Med Sci. 2019;358(6):422-8.
- Zhai Q, Wang X, Chen C, et al. Prognostic Value of Plasma Trimethylamine N-Oxide Levels in Patients with Acute Ischemic Stroke. Cell Mol Neurobiol. 2019;39(8):1201-6.
- Del Rio D, Zimetti F, Caffarra P, et al. The Gut Microbial Metabolite Trimethylamine-N-Oxide Is Present in Human Cerebrospinal Fluid. Nutrients. 2017;9(10):1053.
- Vogt NM, Romano KA, Darst BF, et al. The gut microbiota-derived metabolite trimethylamine N-oxide is elevated in Alzheimer's disease. Alzheimers Res Ther. 2018;10(1):124.
- Zhuang R, Ge X, Han L, et al. Gut microbe-generated metabolite trimethylamine N-oxide and the risk of diabetes: A systematic review and dose-response meta-analysis. Obes Rev. 2019;20(6):883-94.
- Ottiger M, Nickler M, Steuer C, et al. Trimethylamine-N-oxide (TMAO) predicts fatal outcomes in community-acquired pneumonia patients without evident coronary artery disease. Eur J Intern Med. 2016;36:67-73.
- Missailidis C, Hällqvist J, Qureshi AR, et al. Serum Trimethylamine-N-Oxide Is Strongly Related to Renal Function and Predicts Outcome in Chronic Kidney Disease. PLoS One. 2016;11(1):e0141738.
- Smits LP, Kootte RS, Levin E, et al. Effect of Vegan Fecal Microbiota Transplantation on Carnitine- and Choline-Derived Trimethylamine-N-Oxide Production and Vascular Inflammation in Patients With Metabolic Syndrome. J Am Heart Assoc. 2018;7(7):e008342.
- Koeth RA, Wang Z, Levison BS, et al. Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med. 2013;19(5):576-85.
- Koeth RA, Lam-Galvez BR, Kirsop J, et al. l-Carnitine in omnivorous diets induces an atherogenic gut microbial pathway in humans. J Clin Invest. 2019;129(1):373-87.
Video production by Glass Entertainment
Motion graphics by Avo Media
- Alzheimer’s disease
- animal products
- arthritis
- brain health
- butyrate
- cardiovascular disease
- carnitine
- cheese
- choline
- cognition
- COPD
- dairy
- dementia
- diabetes
- DNA damage
- eggs
- fecal transplant
- fiber
- gut flora
- heart disease
- kidney disease
- kidney function
- meat
- microbiome
- oxidative stress
- PCOS
- Plant-Based Diets
- pneumonia
- seafood
- stroke
- TMAO
- vegans
- vegetarians
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Can Vegan Fecal Transplants Lower TMAO Levels?
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Content URLDoctor's Note
Want to become a donor? Find out How to Become a Fecal Transplant Super Donor.
For more on TMAO, check out:
- Eggs, Choline, and Cancer
- Carnitine, Choline, Cancer, and Cholesterol: The TMAO Connection
- Egg Industry Response to Choline and TMAO
- How to Develop a Healthy Gut Ecosystem
- How to Treat Heart Failure and Kidney Failure with Diet
- How to Reduce Your TMAO Levels
See the microbiome topic page for even more.
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