Marked elevation in plasma trimethylamine N oxide (TMAO) in patients with mitochondrial disorders treated with oral l carnitine ScienceDirect Intestinal microbiota metabolism of l carnitine, a nutrient in red meat, promotes atherosclerosis Nature Medicine Dietary allicin reduces transformation of L carnitine to TMAO through impact on gut microbiota ScienceDirect L Carnitine intake and high trimethylamine N oxide plasma levels correlate with low aortic lesions in ApoE transgenic mice expressing CETP Atherosclerosis Characterization of TMAO productivity from carnitine challenge facilitates personalized nutrition and microbiome signatures discovery Microbiome Springer Nature Link