Amazon.com: Designs for Health NAC 900mg N Acetyl L Cysteine, Antioxidant Glutathione Precursor Detox + Workout Recovery Support Non GMO + Gluten Free Supplement (120 Capsules) : Health & Household Metabolic Maintenance NAC NAD vs NAC: Key Differences and Benefits Explained Goldman N Acetyl Cysteine Functions as a Fast Acting Antioxidant by Triggering Intracellular H2S and Sulfane Sulfur Production: Cell Chemical Biology As I mention in my book, N acetyl cysteine (NAC) is not found in food sources, but in the body, it converts into cysteine. NAC acts as a precursor to glutathione, a powerful NAC vs Glutathione: Comparing Antioxidant Powerhouses for Your Health IVDrips