Eating a lot of a common nutrient found in a variety of foods — including meat, eggs and milk — raises your risk of clots, new data suggest.

The study, published in the American Heart Association journal Circulation, provides the first direct evidence in humans that consuming excess choline, an essential nutrient plentiful in a Western diet, increases levels of a bacteria-produced compound called trimethylamine N-oxide, or TMAO, and the tendency of platelets to clump together and form clots.

Excessive blood clotting limits or blocks blood flow, which can cause heart attacks, strokes, damage to the body’s organs or death.

Numerous studies have shown that higher blood levels of TMAO are associated with a greater risk of heart disease, including heart attacks and strokes in humans, and recent studies showed that feeding animals choline-supplemented diets also raised their risk of clotting.

In the small study, eight vegans or vegetarians and 10 omnivores without heart disease or major risk factors took 500 milligrams of choline bitartrate twice daily for two months. The average daily intake is about 302 mg a day.

After one and two months of choline supplementation in vegans/vegetarians and omnivores, blood levels of TMAO rose more than 10 times and the tendency of platelets to form clots in a laboratory test increased.

The ability of elevated TMAO levels to promote clot formation was reduced when subjects were also taking a daily baby aspirin (81 mg per day), researchers said.

“Foods that raise TMAO may increase your risk for clotting and thrombotic events,” said Stanley L. Hazen, M.D., Ph.D., chair of Cellular and Molecular Medicine and section head of Preventive Cardiology & Rehabilitation at the Cleveland Clinic in Ohio. “Unless prescribed by your doctor, avoid supplements with choline. A Mediterranean or vegetarian diet is reported to help reduce TMAO.”