What are Glutathione Benefits? Uses & Side effects 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), Glutathione (GSH) and NAD are both critical for cellular health, energy, and repair. Yet, they function very differently in the body. The question I'm often asked is, "Which one do I need The Biological Functions of Glutathione Encyclopedia MDPI