L-arginine is a vital amino acid in the body that is used in wound healing, removing waste products from the body, and in maintaining proper immune and hormone function. As you already know, it can also help boost nitric oxide production in the body, relaxing blood vessels and thus improving blood flow and leading to better heart health. Recent research suggests that l-arginine can also build lean tissue.
Researchers have found that l-arginine supplementation can help the body decrease fat production. It was found that it can also promote muscle growth. Researchers suggest that l-arginine utilizes energy from the diet and puts it toward muscle gain rather than fat production. Along with this, a 2009 study showed that this natural amino acid reduced fat gain in rats and increased muscle growth in pigs. This goes to show that the amino acid l-arginine has significant weight loss benefits, as well as muscle gain benefits too.