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 Made Simple: A Guide to Glutathione, Detox, and Rejuvenation Kindle edition by Green, Neil C. Health, Fitness & Dieting Kindle eBooks @ Amazon.com. N Acetyl Cysteine (NAC) + Glycine 800mg 60 Caps How do glutathione and Nacetylcysteine (NAC) compare regarding indications, dosing, effectiveness, and safety for acetaminophen toxicity, mucolytic therapy, and general antioxidant supplementation? Glutathione vs. NAC: Why You Should Take NAC for Better Absorption Can N acetylcysteine (NAC) Supplements Increase Cellular Glutathione Glyteine