Amino acid precursor of nitric oxide associated with promoting cardiovascular health, immune support, sexual function, and memory | L-Arginine supports nitric oxide formation, important for healthy dilation of blood vessels, circulation, and blood flow. In trials, L-arginine has demonstrated the potential to support endothelial function in blood vessels, platelet function, exercise tolerance, and sexual function. Because of its effect on nitric oxide production, L-arginine is theoretically best avoided by individuals with migraines, depression, autoimmune disorders, and kidney or liver disease. L-Arginine is contraindicated for individuals with the herpes virus.