L-ornithine is a non-essential amino acid. It plays an important role as an intermediate in the urea cycle, a critical body function that helps eliminate excess nitrogen and ammonia, as well as synthesize arginine—another important amino acid—in your body. L-ornithine supplements are also often used to promote vascular health. Like other aminos, L-ornithine is predominantly found in meat, fish, dairy and eggs. Think this amino acid may benefit you? Learn more in the customer reviews below.