You already know about the traditional risk factors for heart disease, including high blood pressure and elevated blood levels of cholesterol, triglycerides, and glucose. But were you aware of how the trillions of friendly bacteria living in your gut influence heart health? Research about how the gut relates to the heart can help you make smarter food choices.
Goal: Clear and Flexible Arteries
A compound called TMAO (trimethylamine N-oxide) provides the strongest evidence for a link between the gut and the heart. High levels of TMAO in the blood are associated with a greater risk for cardiovascular disease, even in the absence of known risk factors, such as high blood cholesterol, that play a role in the formation of plaque that blocks the flow of blood to the heart and elsewhere. Researchers think that TMAO may also harm arteries by contributing to plaque buildup as well as stiffness in the arteries, which increases blood pressure.
TMAO Starts in the Gut
The production of TMAO begins in the gut where bacteria create TMA (trimethylamine) from choline and carnitine found in food. Animal foods provide most of the carnitine in the American diet, but the amount varies widely. For example, 3 ounces of cooked ground beef contains up to 74 milligrams of carnitine, while the same amount of cooked chicken breast or cod has about 4 milligrams.
Choline and creatine are found together in higher amounts in animal foods, particularly red meat such as beef, pork, and lamb. Research shows that switching from red meat to white meat (such as chicken or turkey) or a plant-based protein source lowers TMAO levels in just 4 weeks. However, the same study also showed that the choline in red meat didn’t increase the production of TMA in the gut, suggesting that carnitine may be more problematic than choline. Another study concluded that the form of choline matters when it comes to TMAO levels. People who ate four eggs – one of the richest choline sources – daily didn’t have increased TMAO levels, but those taking choline bitartrate supplements did see a rise.
Some foods help prevent TMA formation. Research conducted with animals found that DMB, a compound in plant foods including cold-press olive oil, balsamic vinegar, red wine, and grape seed oils, interfered with TMA formation and lowered TMAO in the bloodstream.
