Can you get too much choline?

The Tolerable Upper Intake Level for choline is 3,500 mg a day for adults. High intakes cause fishy body odour, vomiting, sweating, low blood pressure and liver toxicity.

What this means for you

In theory yes, in practice almost nobody does. The upper limit is 3,500 mg a day, and average intake in the United States sits around 400 mg for men and 278 mg for women. Getting to the limit from food would mean something like twenty eggs a day.

What excess looks like is memorable rather than subtle. A fishy body odour, sweating, vomiting, low blood pressure and liver toxicity. The odour comes first and is the classic sign of a large supplement dose.

Unsettled. The question people actually worry about is TMAO. Gut bacteria turn some choline into TMA, the liver converts it to TMAO, and higher TMAO has been linked with cardiovascular risk. Several large observational studies have looked for a matching signal in choline intake itself and found no significant association with cardiovascular or peripheral artery disease. A mechanism on its own is a reason to keep studying something, not a reason to avoid eggs.

Given how many people fall short of the recommended amount, especially in pregnancy, the realistic risk with choline runs in the other direction.

The floor and the ceiling were built by different methods

Before worrying about the top of this page, it is worth knowing how soft the bottom of it is. The adult recommendation came from feeding adults a choline-free diet until their livers showed damage and finding that 500 mg a day corrected it. In pregnancy, 480 against 960 mg a day made no consistent difference to outcomes, so nothing in the evidence argues for aiming high. Europe publishes a single 400 mg a day for all adults and teenagers from 15, against the American 550 for men and 425 for women. Each of those is an Adequate Intake, the label a body uses when it could not derive a requirement.

So the shape of this page is lopsided on purpose. There is a real upper limit of 3,500 mg a day with unpleasant effects behind it, and at the other end a recommendation nobody could derive properly. The gap between the two is wide enough that food will not carry you across it. Getting there takes supplements, on purpose, in quantity.

Written from the evidence cards and the data on this page, then checked back against the sources. Bioma Learn has no human medical reviewer at this time and we say so rather than invent one. Information, not medical advice. How we verify.

Upper limits apply to everything you take in, from supplements and, for most nutrients, from food as well. Reaching one from whole food alone is uncommon. Supplements are where people cross the line, usually without meaning to.

Full guide: Choline: the nutrient almost nobody meets, and almost nobody discusses