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 L GLUTATHIONE: A Review of Clinical Studies on its Role in Antioxidant Nourished Asia Figure 1 from The role of glutathione in photosynthetic organisms: emerging functions for glutaredoxins and glutathionylation. Semantic Scholar Glutathione: Master Antioxidant, Reducing Oxidative Stress, and Detoxification