L Carnitine Benefits, Uses, Dosage, Foods, Side Effects Dr. Axe L Carnitine L Tartrate: 8 Key Benefits Dr. Lam Systemic primary carnitine deficiency Wikipedia Symptoms of B12 Lipotropic L Carnitine Deficiency VITAstir IV Therapy & B12 Shots 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.