Characterization of TMAO productivity from carnitine challenge facilitates personalized nutrition and microbiome signatures discovery Microbiome Springer Nature Link Trimethylamine N oxide (TMAO) is a small molecule produced in humans primarily by the gut liver axis and has become an important biomarker, and possible mediator, of cardiometabolic and renal disease. Dietary choline, phosphatidylcholine ( Oolong Tea Extract and Citrus Peel Polymethoxyflavones Reduce Transformation of l Carnitine to Trimethylamine N Oxide and Decrease Vascular Inflammation in l Carnitine Feeding Mice Journal of Agricultural and Food Chemistry Dietary allicin reduces transformation of L carnitine to TMAO through impact on gut microbiota ScienceDirect