L Arginine vs. L Carnitine Come see which nutrient best fits your needs L Carnitine vs L Arginine: Understanding Their Differences and Benefit Fitness Health L Carnitine vs L Arginine: Understanding Their Differences and Benefit Fitness Health L Arginine and L carnitine , Arginine is an amino acid which we can also produce naturally . This increases your notice oxide production , human growth hormone and improves circulation. , These three Nutricost L Arginine L Citrulline Complex Capsules