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 Interaction with Ethanol Alcohol Metabolism N acetylcysteine in Kidney Disease: Molecular Mechanisms, Pharmacokinetics, and Clinical Effectiveness Kidney International Reports Inflammation Springer Nature Link N Acetylcysteine as an antioxidant and disulphide breaking agent: the reasons why Glutathione, N Acetyl Cysteine Amino Acid Supplements