Medical practitioners and researchers have long assumed that cholesterol and saturated fat in red meat increase the risk for cardiovascular problems. A study published in Nature Medicine offers a different explanation. Red meat is packed with a compound, called carnitine, which aids the transportation of fatty acids. The research team found out that carnitine is converted into TMAO by bacteria growing in the digestive tract. This increases the chances of developing atherosclerosis, which causes peripheral vascular disease, stroke, and heart attack.

Other studies link red meat consumption with some types of cancer and heart problems. A report by the Harvard School of Public Health shows that people who consume large amounts of meat are at an increased risk of death. While researchers have linked cardiovascular problems with cholesterol and saturated fat, the new study offers another explanation. According to experts, TMAO is a compound that changes the way in which cholesterol is metabolized (processed). TMAO affects the bodies of vegans and meat eaters in different ways. TMAO levels rise and bacteria increase in number in the bodies of meat eaters. There are no bacterial changes or an increase in TMAO in vegans.

Previously, the research team of Dr Hazen found out that substances in choline are transformed by bacteria in the intestines into TMAO. The new research focused on l-carnitine, a compound found in dairies, milk, poultry, and red meat. Red meat contains more of it compared to other products. Some muscle milks, energy drinks, and diet supplements also contain carnitine. The new study followed 2,600 women and men and checked carnitine at fasting levels. Higher levels of carnitine increase the risk of death, stroke, and heart attack within a 3-year period. The regular consumption of products that contain carnitine changes the metabolism of cholesterol, and smaller amounts of it are eliminated. This means that cholesterol is deposited on the walls of the blood vessels. Researchers recommend decreasing portion size and eating red meat less frequently. Taking supplements that contain carnitine may also increase the long-term risk for cardiovascular problems.