Healthy Protein Metabolism* Ornithine is a non-essential amino acid that plays a central role in the urea cycle, functioning along with arginine and citrulline to rid the body of ammonia, a byproduct of protein metabolism.* Because ornithine is converted into arginine, it can help to maintain healthy arginine levels in the body.* Ornithine can also be converted into other amino acids, such as citrulline, proline, and glutamate, as well as creatine, an important muscular energy source.* Natural color variation may occur in this product.