A peptide composed of cysteine, glycine, and glutamate. It is believed to enhance the skin’s cellular metabolism and oxygen utilization. It has been found to protect the fibroblast against free radical-induced oxidation and act as a powerful antioxidant. Studies indicate that it can inactivate the tyrosinase enzyme and quench free radicals that contribute to tyrosinase and melanin formation, thereby serving as a skin-lightening or depigmenting agent. Glutathione is a component of plant and animal tissue, naturally occurring in the body and essential for the proper functioning of the immune system.