Arginine, a semi-essential amino acid, is particularly abundant in meats, whole grains, and dairy products 1. Under normal conditions the body can synthesize sufficient arginine to meet physiological needs. Stress conditions put an increased demand on the body for arginine and, under these conditions, dietary arginine becomes essential 2, 3. According to the U.S. Food and Drug Administration (FDA), arginine can be safely added to foods (21CFR172.320). Arginine can also be used as a skin conditioning agent in cosmetics and skin care products 4.