Glutathione, NAC & Vitamin C 30 Veg caps Glutathione, NAC & Vitamin C 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 Amazon.com: DEAL SUPPLEMENT NAC Supplement (N Acetyl Cysteine) 1,000mg Per Serving with Reduced Glutathione, 240 Capsules Antioxidant Support for Immune Health, Lung, & Liver Function : Health & Household NAC (N acetyl cysteine) is a powerful compound that plays an important role in supporting the body's natural detoxification and antioxidant systems. One of its key functions is helping the body produce glutathione, Glutathione Vs NAC: Which is Best for Skin?