Elucidation of an anaerobic pathway for metabolism of l carnitinederived butyrobetaine to trimethylamine in human gut bacteria PNAS Differential effects of oral and intravenous L carnitine on serum lipids: is the microbiota the answer? Characterization of TMAO productivity from carnitine challenge facilitates personalized nutrition and microbiome signatures discovery Microbiome Springer Nature Link What Is Carnitine? TMAO? What's Their Link To Red Meat? Pritikin