Does L Carnitine Cause Heart Problems? Effect of L Carnitine on Oxidative Damage to Liver, Kidney and Spleen Induced by Phenylhydrazine in Mice: Journal of Applied Animal Research: Vol 32, No 1 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 L Carnitine Linus Pauling Institute Oregon State University Biomedical Reports The Importance of the Fatty Acid Transporter L Carnitine in Non Alcoholic Fatty Liver Disease (NAFLD) July 2020 : r ketoscience