L Carnitine Linus Pauling Institute Oregon State University L Carnitine Benefits, Uses, Dosage, Foods, Side Effects Dr. Axe Optimized Carnitine, 60 capsules Life Extension Rexdrive Amino with L Arginine HCl, L Citrulline, Acetyl L Carnitine Arginate DiHydrochloride, and Glycine Swanson Propionyl L Carnitine with Glycine Heart Health and Energy Support, Muscle Strength and Endurance, 60 Veggie Capsules Macy's If you are like a lot of people, you may have never heard of carnitine but this important nutrient is critical for our body's ability to optimally burn fat required for energy.