Intestinal microbiota metabolism of l carnitine, a nutrient in red meat, promotes atherosclerosis Nature Medicine Elucidation of an anaerobic pathway for metabolism of l carnitinederived butyrobetaine to trimethylamine in human gut bacteria PNAS Dietary bioactive ingredients to modulate the gut microbiota derived metabolite TMAO. New opportunities for functional food development Food & Function (RSC Publishing) DOI:10.1039 D0FO01237H Differential effects of oral and intravenous L carnitine on serum lipids: is the microbiota the answer?