14 Glutathione Benefits for Your Body and Health Annex Naturopathic Clinic Glutathione is one of the most powerful antioxidants, naturally synthesized in the body and central to cellular defense. Glutathione supports the effective functioning of the immune system by reducing oxidative damage caused Master Antioxidant" Glutathione Affected by Vitamin D Status GrassrootsHealth Glutathione Benefits, Safety & Myths Explained Glutathione is nicknamed the master antioxidant because it is the most abundant, body produced (endogenous) antioxidant found in every cell, essential for neutralizing free radicals, recycling other antioxidants (like Vitamin C and E),