Full article: Glutathione Improves the Antioxidant Activity of Vitamin C in Human Lens and Retinal Epithelial Cells: Implications for Vitreous Substitutes Glutathione and Vitamin C: Better Together? Performance Lab Glutathione and the Cofactors Glutathione is a small protein made of three amino acids. It is often called the master antioxidant because it helps regenerate other antioxidants like vitamin C and vitamin E. Key Benefits