Frontiers The effect of L carnitine supplementation on lipid profile in adults: an umbrella meta analysis on interventional meta analyses The Importance of the Fatty Acid Transporter L Carnitine in Non Alcoholic Fatty Liver Disease (NAFLD) L carnitine is a naturally occurring amino acid structure that is made in the human brain, liver, and kidneys. L carnitine plays a critical role in energy production, as it converts fat into energy. L Carnitine 3500 Metabolic Nutrition Didn't another study show carnitine was good for the heart? According to a study published in Clinical Therapeutics, in people with type 2 diabetes and high cholesterol, taking L carnitine (1 gram twice daily) for 6 months significantly lowered lipoprotein(a) a genetic,