Heart and Disease: TMA Uh-Oh

Researchers have zeroed in on TMAO, trimethylamine-N-oxide, as a new culprit in heart disease. “We’ve long recognized that two individuals could have the same LDL—or bad—cholesterol, yet one goes on to develop heart disease and one doesn’t,” says the Cleveland Clinic’s Stanley Hazen.


That started the hunt. “First we said, ‘Let’s look at all the compounds in the blood that differ between people who have heart disease and people who don’t,’” recalls Hazen. “And we discovered that TMAO was one of the top things that tracked with risk.” But where did the TMAO come from?

When bacteria in our intestines “eat” carnitine or choline, they make TMA (trimethylamine), which gets converted to TMAO in the liver. Carnitine is found largely in red meat. Egg yolks and liver have the highest levels of choline, but it’s also in meat, poultry, fish, grains, vegetables, and other foods.

“You can’t get away from choline,” says Hazen. “It’s in everything, and you don’t want to completely eliminate it from your diet. If you got absolutely none, you’d get a deficiency, just like you’d get scurvy if you didn’t get any vitamin C. So you can’t eat your way out of that problem.”

Until we know more, you can hedge your bets by cutting back on red meat and ditching supplements of carnitine, choline, or choline’s most common form, phosphatidylcholine (lecithin).

“Unless you’ve been instructed by your physician to take carnitine, which can happen with mitochondrial disorders or with long-term dialysis, you probably don’t need it,” says Hazen. “Your body can make all the carnitine it needs even if you’re a vegan or never eat any meat.”

You don’t need choline supplements either. “Deficiencies are exceedingly rare,” says Hazen. “We just don’t see it in the United States. You have to be very malnourished.”

“There’s a potential for long-term risk from both carnitine and choline,” he adds. “And I know of no clear, hard benefit for an otherwise healthy person. Supplement companies may argue that they’re helpful because they’re nutrients. But cholesterol is a nutrient too, and we don’t take cholesterol tablets.”

And don’t bother asking your doctor to test your TMAO. “Unfortunately, the test isn’t currently available for clinical use,” says Hazen. “It should be before the end of the year [2013].”

Source: www.ars.usda.gov/SP2UserFiles/Place/12354500/Data/Choline/Choln02.pdf.


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12 Replies to “Heart and Disease: TMA Uh-Oh”

  1. Thanks so much for all the great current info. I’m a retired Registered Clinical Dietitian and have been a member of CSPI since the very beginning except for a short time when I was inadvertent.

  2. This information will come as another reason to follow a mostly plant-based (or even entirely vegan) diet. I feel sorry for all the people who dutifully took choline, carnitine, and lecithin supplements in in the mistaken belief that these nutrients helped prevent heart disease. I can recall studying from a biochemistry textbook (was it Voet and Voet?) that advised vegetarians to take supplemental carnitine for heart health! I also remember many health advocates who swore that the J. Rinse formula (a once popular supplement heavy in lecithin and choline) would protect them from heart disease. We live and learn.

  3. I agree. Every time we try to pull out one nutrient and use it as a supplement we risk getting things out of whack. Unfortunately, people are much more inclined to try to “supplement ” themselves to health rather than eat a healthy diet.

  4. If you look closely you’ll find lecithin listed (a choline source which I believe is now categorized as a “B” vitamins)in virtually all daily supplements and in one of the lot of common foods.

    If you want a real eye opener go to this web site, it will give you a good perspective on the thinking about past views of choline and some of it’s sources in our diet.


  5. Just checked my AllOne vitamin from Whole Foods – it contains 350mg Lethicin (as Soy Lethicin) and 100mg Choline (as Choline Bitartrate and Lethicin). If I understand your article, these are actually potentially harmful additions? I will check the labels on the shelves, but it is likely that most vitamins have these ingredients. What is a harmful level – are these quantities so small that they are negligible, or NOT? Please advise!

  6. OK, so they’ve found a correlation. That is NOT a cause and effect relationship. I’m going to refrain from jumping on this bandwagon just yet.

  7. LOL! I thought TMAO was Talk My @ss Off!

    Seriously, another two big factors, according to Dr. Lustig, UCSF and NY Times science writer Gary Taubes (who reports on dietary research), are
    (1) there are two major categories of LDL, type A and type B. Type B, the small, dense LDL is directly linked with atherosclerosis and is caused by eating refined carbohydrates. Type A, the large, fluffy LDL is caused by eating animal protein and fat, and is benign. If your doctor/lab is lazy, they measure total LDL, which doesn’t differentiate between the harmful and the benign LDLs, so it’s no wonder that some people with high LDL get heart attacks and some don’t. There is a strong correlation between high type B LDL and atherosclerosis. There is none for type A LDL. [Sources: Lustig, “Fat Chance, Beating the Odds Against Sugar, Processed Food, Obesity, and Disease”; Taubes, “Good Calories, Bad Calories: Fats, Carbs, and the Controversial Science of Diet and Health”]
    (2) Omega-6 fatty acids are highly correlated to atherosclerosis. Omega-3 fatty acids are very good for us and not correlated with atherosclerosis. Corn and soy-fed animals have approximately 20 times the amount of omega-6 fatty acids in their meat/fat than grass-fed animals. (I’ve read about only cows and pigs. I don’t know about poultry.) The switch to corn as livestock feed happened during the Nixon era when Secretary of Agriculture, Earl Butz switched the farm programs to favor refiners (mainly corn & soy) instead of the farmers. [source: Michael Pollan, The Omnivore’s Dilemma] This correlates with the beginning of the metabolic disease pandemic.

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