Metabolic clues could lead to potential treatment in complex critical illnesses University of Michigan Medical School Acetyl L Carnitine Olympian Labs Acetyl L Carnitine MRM Nutrition Did you know L carnitine, a vital amino acid, is naturally produced by your body and found in various foods? While acetyl L carnitine (ALCAR) can be a beneficial supplement for some, most people get Vitamins, Minerals & Supplements Nutrients Andrew Weil, M.D.