Egg yolk has lecithin, and when you eat lecithin, the body digests lecithin, breaking it into its constituent parts, including the chemical choline. Intestinal bacteria metabolize choline and release a substance that the liver converts to a chemical known as TMAO, for trimethylamine N-oxide. High levels of TMAO in the blood are linked to increased risk of heart attack and stroke.
The more TMAO more likely they were to have a heart attack or stroke in the ensuing three years. Carnitine found in meat also has a similar effects and the heart
Lecithin and choline in their diet, means eating less of foods high in fat and cholesterol. It is best reduce the supplements of carnitine lecithin and choline.
Probiotics are known the reduce the TMAO by changing the bacterial flora and this will reduce the incidence of heart disease. However the specifics of this has not been established