NEW YORK — Researchers have found a surprising new explanation of why red meat may contribute to heart disease.
The study by scientists at the Cleveland Clinic, an academic medical center, discovered that what damages hearts is not just the thick edge of fat on steaks, or the delectable marbling of their tender interiors.
The real culprit may be a little-studied chemical that is burped out by bacteria in the stomach after people eat red meat. It is quickly converted by the liver into yet another little-studied chemical called TMAO that gets into the blood and increases the risk of heart disease.
The results of extensive experiments in both humans and animals, published Sunday in Nature Medicine, have persuaded scientists not connected with the study to seriously consider this new theory of why red meat, eaten too often, might be bad for people.
Tests found that a burst of TMAO shows up in peoples’ blood after they eat steak, but not vegans who had not had meat for at least a year but consumed the same meal. TMAO levels also turned out to predict heart attack risk in humans, the researchers found.
Researchers say the work could lead to new treatments for heart disease — perhaps even an antibiotic to specifically wipe out the bacterial culprit — and also to a new way to assess heart disease risk by looking for TMAO in the blood.