L carnitine is primarily synthesized in the liver from the amino acids lysine and methionine through a series of four enzymatic reactions, with the liver and kidneys converting the precursor butyrobetaine into active Fatty Acid Metabolism Concise Medical Knowledge Fatty Acid Transport an overview ScienceDirect Topics Comprehensive review of the expanding roles of the carnitine pool in metabolic physiology: beyond fatty acid oxidation Journal of Translational Medicine Springer Nature Link The Role of l Carnitine in Mitochondria, Prevention of Metabolic Inflexibility and Disease Initiation The Importance of the Fatty Acid Transporter L Carnitine in Non Alcoholic Fatty Liver Disease (NAFLD)