NAC and Glutathione: The Amino Acid the Supplement Industry Is Not Telling You About Potential Role of Glutathione Antioxidant Pathways in the Pathophysiology and Adjunct Treatment of Psychiatric Disorders 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 Glutathione Precursor, N Acetyl Cysteine, Improves Mismatch Negativity in Schizophrenia Patients Neuropsychopharmacology L Glutathione VS NAC: Differences, Similarities, and Uses