If you only take one antioxidant, make it glutathione. This powerful tripeptide is the body's master antioxidant and detoxifier. Present within every cell, glutathione is your body's primary defense molecule. Production within the body declines with age, and most supplements are not stable enough to be effective. Japanese-produced pharmaceutical-grade Setria is guaranteed stable and highly absorbable. Swanson L-Glutathione features 500 mg of Setria per serving.