L carnitine helps transport fatty acids into your cells' mitochondria, where they can be used for energy. That's why it's often marketed for fat loss and energy support. Common use: People usually take L Carnitine L Tartrate Capsules Get Fit & Tone Up L Carnitine Benefits for Fat Burning and How to Use ICONFIT Amazon.com: NOW Foods Supplements, L Carnitine 1,000 mg, Purest Form, Amino Acid, Fitness Support*, 100 Tablets : Health & Household How Much L Carnitine Per Day: Expert Guide The Science of Good Health When to Take L Carnitine for Weight Loss & Maximize Results