Glutathione, a tripeptide found in virtually all cells, functions as a reducing agent. The structure of glutathione is: What amino acids make up glutathione? Homework.Study.com Glutathione The Master Antioxidant With Enormous Benefits Wellness By Rosh Integrative Wellness What Is Glutathione? A Summary of Glutathione Lifespan Research Institute What are the three amino acids that make up glutathione? Glutathione is the body's primary internal antioxidant, made using the amino acid cysteine, and it helps protect cells from oxidative stress. Beyond detoxification, research shows glutathione is involved in thyroid hormone metabolism,