The essential amino acid histidine is probably best known as a precursor to histamine, a substance integral to a healthy immune system. But histidine does much more. It's essential for iron uptake. It's needed to form the body's most prolific antioxidant Superoxide Dismutase (SOD). It even facilitates the transportation of trace elements. While most people get plenty of histidine in their diets, healthcare providers recommend supplements for those in need of a little boost. Our vegetarian- source AjiPure L-Histidine is produced by Ajinomoto AminoScience, the world leader in pharmaceutical grade aminos.