Many studies have shown that people who eat diets high in red meat have a higher risk of heart disease and stroke than those who eat little red meat. For years, saturated fat has been suggested to be the reason, but that link has been hard to prove. In a new study published in the journal Nature Microbiology, researchers at the Cleveland Clinic found that a particular bacteria found in the gut microbiome might be involved. They found that frequent red-meat eaters have more of a group of bacteria called Emergencia timonensis. This bacteria turns carnitine, a common nutrient in food, into a chemical called TMAO. TMAO has been linked to blood clotting. When people eat less red meat and more white meat or vegetable protein, such as in the Mediterranean diet, they have less TMAO in their blood.