What Is Glutathione & Its Uses Health Tip on Glutathione Can Boost Immune System Roles of glutathione in animals Antioxidant defense Download Table Glutathione: Biosynthesis, Functions and Biological Implications Glutathione is an amino acid and that acts as a powerful antioxidant to preserve and protect the brain and other body tissues by protecting them from the damage of free radicals and Glutathione: your body's master antioxidant & detoxifier Glutathione is the 2nd most abundant molecule in the body, just after water. Its made from three amino acids: glycine, cysteine, & glutamate.