Should we be concerned about high-choline plant foods, such as broccoli, producing the same toxic TMAO that results from eating high-choline animal foods, such as eggs?
How to Reduce Your TMAO Levels
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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.
Choline and carnitine-rich foods—meat, eggs, and dairy—can be converted by gut flora into trimethylamine, which can then be turned into TMAO in our liver—a toxic compound which may increase our risk of heart failure, kidney failure, and atherosclerosis (heart attacks and strokes). The good news is, though, that this “opens up exciting new nutritional and interventional prospects” for prevention.
Okay, so how are we going to do it? If our gut bacteria can take meat, dairy, and eggs and turn them into TMAO, all we have to do is destroy our gut flora. We could give people “antibiotics to eliminate the production of” TMAO. However, that could also kill our good bacteria, and “facilitate the emergence of antibiotic-resistant…strains.”
Hmm. How about probiotic supplements? Maybe if we add good bacteria, it will crowd out the ones that take the meat, egg, and dairy compounds, and turn them into TMA, which our liver turns into TMAO. But, it doesn’t work. Adding good bacteria doesn’t seem to get rid of the bad.
What if we added a new bacteria that could somehow siphon off the TMA made by the bad bacteria? Well, there’s a bacteria inside the guts of cows and sheep that turns trimethylamine into methane. So, maybe we could use the bacteria to get rid of some of it from our gut, like a cow fecal transplant. The problem is, if it didn’t take, you’d have to keep giving it to people. So, maybe the fact that Consumer Reports found “fecal contamination” in every sample of beef they tested may be a good thing! No. Methane-producing bacteria may be able to eat up our TMAO, but unfortunately, these bacteria may be associated with a variety of diseases, from gum disease down to colorectal cancer.
So, if antibiotics and probiotics aren’t going to work to prevent gut bacteria from taking meat, dairy, and eggs, and turning them into the trimethylamine which our liver makes TMAO out of, I guess we have no choice but to cut down on—our liver function!
That was the billion-dollar answer to cholesterol. These same foods raise our cholesterol, but dietary change isn’t very profitable. So, the drug industry came up with statin drugs that cripple the liver enzyme that makes cholesterol. So, hey, “pharmacologic inhibition of” the enzymes in our liver that make TMAO could “potentially serve as a therapy for [cardiovascular disease] risk reduction.” But, there’s a genetic condition in which this enzyme is naturally impaired, called trimethylaminuria, in which there is a buildup of trimethylamine in the bloodstream. The problem with that is that trimethylamine is so stinky, it makes you smell “like dead fish.” So, “given the known adverse effects…from sufferers of [this] fish odor syndrome, the untoward odorous side effects…make it a less attractive [drug] target.” So, do we have to choose between smelling like dead fish, or suffering from heart and kidney disease?
If only there was some other way we could somehow stop this process from happening. Well, what do those with trimethylaminuria often do to cut down trimethylamine levels? They stop eating animal products.
About a third of those who complain of really bad BO, despite good personal hygiene, test positive for the condition, but reducing or eliminating meat, egg, and dairy intake can be a real lifesaver. But, given what we now know about how toxic the end product TMAO can be for normal people, cutting down on animal products may not just save the social lives of people with a rare genetic disorder, but help save everyone else’s actual lives.
“The simplest point of intervention is to [just] limit [the] consumption of” foods rich in choline and L-carnitine, which can be an effective strategy to limit circulating TMAO. But, wait, we could always try to genetically engineer a bacteria that eats up trimethylamine, but the simplest, safest recommendation may just be to eat healthier. You can completely eliminate carnitine from the diet, since our body makes all we need. But choline is an essential nutrient. So, we need some, and we can get all we need in fruits, vegetables, beans, and nuts. “However, excess choline, such as that found in eggs, may be worth avoiding.”
Need we worry about high-choline plant foods, like broccoli? Cruciferous vegetable consumption is associated with a significantly longer life: less cardiovascular disease mortality. To see what was going on, researchers took the vegetable highest in choline, Brussels sprouts, and had people eat two cups a day for three weeks, and their TMAO levels actually went down. It turns out that Brussels sprouts appear to downregulate that TMAO liver enzyme naturally—not enough to make you stinky, but just enough to drop TMAO.
And, people who eat completely plant-based may not make any TMAO at all—even if you try. You can give a vegan a steak, which contains choline and carnitine, and not even a bump in TMAO, since vegetarians and vegans have different gut microbial communities. If we don’t eat steak, then we don’t foster the growth of steak-eating bacteria in our gut. So, hey, forget the cow—how about getting a fecal transplant from a vegan? From a TMAO standpoint, maybe we don’t have to eat like a vegan, as long as we poop like one.
Please consider volunteering to help out on the site.
- Wise PM, Eades J, Tjoa S, Fennessey PV, Preti G. Individuals reporting idiopathic malodor production: demographics and incidence of trimethylaminuria. Am J Med. 2011 Nov;124(11):1058-63.
- Tripolt NJ, Leber B, Triebl A, Köfeler H, Stadlbauer V, Sourij H. Effect of Lactobacillus casei Shirota supplementation on trimethylamine-N-oxide levels in patients with metabolic syndrome: An open-label, randomized study. Atherosclerosis. 2015 Sep;242(1):141-4.
- Ferguson JF. Meat-loving microbes: do steak-eating bacteria promote atherosclerosis? Circ Cardiovasc Genet. 2013 Jun;6(3):308-9.
- Gaci N, Borrel G, Tottey W, O'Toole PW, Brugère JF. Archaea and the human gut: new beginning of an old story. World J Gastroenterol. 2014 Nov 21;20(43):16062-78.
- Brown JM, Hazen SL. The gut microbial endocrine organ: bacterially derived signals driving cardiometabolic diseases. Annu Rev Med. 2015;66:343-59.
- Mendelsohn AR, Larrick JW. Dietary modification of the microbiome affects risk for cardiovascular disease. Rejuvenation Res. 2013 Jun;16(3):241-4.
- Brugère JF, Borrel G, Gaci N, Tottey W, O'Toole PW, Malpuech-Brugère C. Archaebiotics: proposed therapeutic use of archaea to prevent trimethylaminuria and cardiovascular disease. Gut Microbes. 2014 Jan-Feb;5(1):5-10.
- Koeth RA, Wang Z, Levison BS, Buffa JA, Org E, Sheehy BT, Britt EB, Fu X, Wu Y, Li L, Smith JD, DiDonato JA, Chen J, Li H, Wu GD, Lewis JD, Warrier M, Brown JM, Krauss RM, Tang WH, Bushman FD, Lusis AJ, Hazen SL. Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med. 2013 May;19(5):576-85.
- Tang WH, Hazen SL. The contributory role of gut microbiota in cardiovascular disease. J Clin Invest. 2014 Oct;124(10):4204-11.
- Wang Z, Klipfell E, Bennett BJ, Koeth R, Levison BS, Dugar B, Feldstein AE, Britt EB, Fu X, Chung YM, Wu Y, Schauer P, Smith JD, Allayee H, Tang WH, DiDonato JA, Lusis AJ, Hazen SL. Gut flora metabolism of phosphatidylcholine promotes cardiovascular disease. Nature. 2011 Apr 7;472(7341):57-63.
- Busby MG, Fischer L, da Costa KA, Thompson D, Mar MH, Zeisel SH. Choline- and betaine-defined diets for use in clinical research and for the management of trimethylaminuria. J Am Diet Assoc. 2004 Dec;104(12):1836-45.
- Cashman JR, Xiong Y, Lin J, Verhagen H, van Poppel G, van Bladeren PJ, Larsen-Su S, Williams DE. In vitro and in vivo inhibition of human flavin-containing monooxygenase form 3 (FMO3) in the presence of dietary indoles. Biochem Pharmacol. 1999 Sep 15;58(6):1047-55.
- Ferrari ND 3rd, Nield LS. Smelling like dead fish: a case of trimethylaminuria in an adolescent. Clin Pediatr (Phila). 2006 Nov;45(9):864-6.
- Koeth RA, Wang Z, Levison BS, Buffa JA, Org E, Sheehy BT, Britt EB, Fu X, Wu Y, Li L, Smith JD, DiDonato JA, Chen J, Li H, Wu GD, Lewis JD, Warrier M, Brown JM, Krauss RM, Tang WH, Bushman FD, Lusis AJ, Hazen SL. Supplemental materials for: Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med. 2013 May;19(5):576-85.
- Neill AR, Grime DW, Dawson RM. Conversion of choline methyl groups through trimethylamine into methane in the rumen. Biochem J. 1978 Mar 15;170(3):529-35.
- Zhang X, Shu XO, Xiang YB, Yang G, Li H, Gao J, Cai H, Gao YT, Zheng W. Cruciferous vegetable consumption is associated with a reduced risk of total and cardiovascular disease mortality. Am J Clin Nutr. 2011 Jul;94(1):240-6.
Image credit: Sally Plank via Flickr. Image has been modified.
Motion graphics by Avocado Video.
- animal products
- antibiotics
- beans
- beef
- broccoli
- Brussels sprouts
- cardiovascular disease
- carnitine
- cholesterol
- choline
- Consumers Union
- cruciferous vegetables
- dairy
- eggs
- fecal transplant
- fruit
- gut flora
- heart disease
- industry influence
- kidney disease
- kidney failure
- legumes
- liver health
- longevity
- meat
- microbiome
- nuts
- Plant-Based Diets
- probiotics
- stroke
- supplements
- TMAO
- vegans
- vegetables
- 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.
Choline and carnitine-rich foods—meat, eggs, and dairy—can be converted by gut flora into trimethylamine, which can then be turned into TMAO in our liver—a toxic compound which may increase our risk of heart failure, kidney failure, and atherosclerosis (heart attacks and strokes). The good news is, though, that this “opens up exciting new nutritional and interventional prospects” for prevention.
Okay, so how are we going to do it? If our gut bacteria can take meat, dairy, and eggs and turn them into TMAO, all we have to do is destroy our gut flora. We could give people “antibiotics to eliminate the production of” TMAO. However, that could also kill our good bacteria, and “facilitate the emergence of antibiotic-resistant…strains.”
Hmm. How about probiotic supplements? Maybe if we add good bacteria, it will crowd out the ones that take the meat, egg, and dairy compounds, and turn them into TMA, which our liver turns into TMAO. But, it doesn’t work. Adding good bacteria doesn’t seem to get rid of the bad.
What if we added a new bacteria that could somehow siphon off the TMA made by the bad bacteria? Well, there’s a bacteria inside the guts of cows and sheep that turns trimethylamine into methane. So, maybe we could use the bacteria to get rid of some of it from our gut, like a cow fecal transplant. The problem is, if it didn’t take, you’d have to keep giving it to people. So, maybe the fact that Consumer Reports found “fecal contamination” in every sample of beef they tested may be a good thing! No. Methane-producing bacteria may be able to eat up our TMAO, but unfortunately, these bacteria may be associated with a variety of diseases, from gum disease down to colorectal cancer.
So, if antibiotics and probiotics aren’t going to work to prevent gut bacteria from taking meat, dairy, and eggs, and turning them into the trimethylamine which our liver makes TMAO out of, I guess we have no choice but to cut down on—our liver function!
That was the billion-dollar answer to cholesterol. These same foods raise our cholesterol, but dietary change isn’t very profitable. So, the drug industry came up with statin drugs that cripple the liver enzyme that makes cholesterol. So, hey, “pharmacologic inhibition of” the enzymes in our liver that make TMAO could “potentially serve as a therapy for [cardiovascular disease] risk reduction.” But, there’s a genetic condition in which this enzyme is naturally impaired, called trimethylaminuria, in which there is a buildup of trimethylamine in the bloodstream. The problem with that is that trimethylamine is so stinky, it makes you smell “like dead fish.” So, “given the known adverse effects…from sufferers of [this] fish odor syndrome, the untoward odorous side effects…make it a less attractive [drug] target.” So, do we have to choose between smelling like dead fish, or suffering from heart and kidney disease?
If only there was some other way we could somehow stop this process from happening. Well, what do those with trimethylaminuria often do to cut down trimethylamine levels? They stop eating animal products.
About a third of those who complain of really bad BO, despite good personal hygiene, test positive for the condition, but reducing or eliminating meat, egg, and dairy intake can be a real lifesaver. But, given what we now know about how toxic the end product TMAO can be for normal people, cutting down on animal products may not just save the social lives of people with a rare genetic disorder, but help save everyone else’s actual lives.
“The simplest point of intervention is to [just] limit [the] consumption of” foods rich in choline and L-carnitine, which can be an effective strategy to limit circulating TMAO. But, wait, we could always try to genetically engineer a bacteria that eats up trimethylamine, but the simplest, safest recommendation may just be to eat healthier. You can completely eliminate carnitine from the diet, since our body makes all we need. But choline is an essential nutrient. So, we need some, and we can get all we need in fruits, vegetables, beans, and nuts. “However, excess choline, such as that found in eggs, may be worth avoiding.”
Need we worry about high-choline plant foods, like broccoli? Cruciferous vegetable consumption is associated with a significantly longer life: less cardiovascular disease mortality. To see what was going on, researchers took the vegetable highest in choline, Brussels sprouts, and had people eat two cups a day for three weeks, and their TMAO levels actually went down. It turns out that Brussels sprouts appear to downregulate that TMAO liver enzyme naturally—not enough to make you stinky, but just enough to drop TMAO.
And, people who eat completely plant-based may not make any TMAO at all—even if you try. You can give a vegan a steak, which contains choline and carnitine, and not even a bump in TMAO, since vegetarians and vegans have different gut microbial communities. If we don’t eat steak, then we don’t foster the growth of steak-eating bacteria in our gut. So, hey, forget the cow—how about getting a fecal transplant from a vegan? From a TMAO standpoint, maybe we don’t have to eat like a vegan, as long as we poop like one.
Please consider volunteering to help out on the site.
- Wise PM, Eades J, Tjoa S, Fennessey PV, Preti G. Individuals reporting idiopathic malodor production: demographics and incidence of trimethylaminuria. Am J Med. 2011 Nov;124(11):1058-63.
- Tripolt NJ, Leber B, Triebl A, Köfeler H, Stadlbauer V, Sourij H. Effect of Lactobacillus casei Shirota supplementation on trimethylamine-N-oxide levels in patients with metabolic syndrome: An open-label, randomized study. Atherosclerosis. 2015 Sep;242(1):141-4.
- Ferguson JF. Meat-loving microbes: do steak-eating bacteria promote atherosclerosis? Circ Cardiovasc Genet. 2013 Jun;6(3):308-9.
- Gaci N, Borrel G, Tottey W, O'Toole PW, Brugère JF. Archaea and the human gut: new beginning of an old story. World J Gastroenterol. 2014 Nov 21;20(43):16062-78.
- Brown JM, Hazen SL. The gut microbial endocrine organ: bacterially derived signals driving cardiometabolic diseases. Annu Rev Med. 2015;66:343-59.
- Mendelsohn AR, Larrick JW. Dietary modification of the microbiome affects risk for cardiovascular disease. Rejuvenation Res. 2013 Jun;16(3):241-4.
- Brugère JF, Borrel G, Gaci N, Tottey W, O'Toole PW, Malpuech-Brugère C. Archaebiotics: proposed therapeutic use of archaea to prevent trimethylaminuria and cardiovascular disease. Gut Microbes. 2014 Jan-Feb;5(1):5-10.
- Koeth RA, Wang Z, Levison BS, Buffa JA, Org E, Sheehy BT, Britt EB, Fu X, Wu Y, Li L, Smith JD, DiDonato JA, Chen J, Li H, Wu GD, Lewis JD, Warrier M, Brown JM, Krauss RM, Tang WH, Bushman FD, Lusis AJ, Hazen SL. Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med. 2013 May;19(5):576-85.
- Tang WH, Hazen SL. The contributory role of gut microbiota in cardiovascular disease. J Clin Invest. 2014 Oct;124(10):4204-11.
- Wang Z, Klipfell E, Bennett BJ, Koeth R, Levison BS, Dugar B, Feldstein AE, Britt EB, Fu X, Chung YM, Wu Y, Schauer P, Smith JD, Allayee H, Tang WH, DiDonato JA, Lusis AJ, Hazen SL. Gut flora metabolism of phosphatidylcholine promotes cardiovascular disease. Nature. 2011 Apr 7;472(7341):57-63.
- Busby MG, Fischer L, da Costa KA, Thompson D, Mar MH, Zeisel SH. Choline- and betaine-defined diets for use in clinical research and for the management of trimethylaminuria. J Am Diet Assoc. 2004 Dec;104(12):1836-45.
- Cashman JR, Xiong Y, Lin J, Verhagen H, van Poppel G, van Bladeren PJ, Larsen-Su S, Williams DE. In vitro and in vivo inhibition of human flavin-containing monooxygenase form 3 (FMO3) in the presence of dietary indoles. Biochem Pharmacol. 1999 Sep 15;58(6):1047-55.
- Ferrari ND 3rd, Nield LS. Smelling like dead fish: a case of trimethylaminuria in an adolescent. Clin Pediatr (Phila). 2006 Nov;45(9):864-6.
- Koeth RA, Wang Z, Levison BS, Buffa JA, Org E, Sheehy BT, Britt EB, Fu X, Wu Y, Li L, Smith JD, DiDonato JA, Chen J, Li H, Wu GD, Lewis JD, Warrier M, Brown JM, Krauss RM, Tang WH, Bushman FD, Lusis AJ, Hazen SL. Supplemental materials for: Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med. 2013 May;19(5):576-85.
- Neill AR, Grime DW, Dawson RM. Conversion of choline methyl groups through trimethylamine into methane in the rumen. Biochem J. 1978 Mar 15;170(3):529-35.
- Zhang X, Shu XO, Xiang YB, Yang G, Li H, Gao J, Cai H, Gao YT, Zheng W. Cruciferous vegetable consumption is associated with a reduced risk of total and cardiovascular disease mortality. Am J Clin Nutr. 2011 Jul;94(1):240-6.
Image credit: Sally Plank via Flickr. Image has been modified.
Motion graphics by Avocado Video.
- animal products
- antibiotics
- beans
- beef
- broccoli
- Brussels sprouts
- cardiovascular disease
- carnitine
- cholesterol
- choline
- Consumers Union
- cruciferous vegetables
- dairy
- eggs
- fecal transplant
- fruit
- gut flora
- heart disease
- industry influence
- kidney disease
- kidney failure
- legumes
- liver health
- longevity
- meat
- microbiome
- nuts
- Plant-Based Diets
- probiotics
- stroke
- supplements
- TMAO
- vegans
- vegetables
- vegetarians
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Title
How to Reduce Your TMAO Levels
LicenseCreative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Content URLDoctor's Note
Can you hear the frustration in my voice as I read paper after paper proposing those ridiculous (but profitable!) answers when the safe, simple, side-effect-free solution was staring them in the face the whole time? Makes me think of so many parallels, not the least of which are:
- How Not to Die from Heart Disease
- How Not to Die from Diabetes
- How Not to Die from High Blood Pressure
- How Not to Die from Cancer
- How Not to Die from Kidney Disease
For more on TMAO, the “smoking gun” of diet-microbiome-disease interactions, see:
- 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
- Can Vegan Fecal Transplants Lower TMAO Levels?
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