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 The mechanism of action of N acetylcysteine (NAC): The emerging role of H2S and sulfane sulfur species ScienceDirect The Central Nervous System Modulatory Activities of N Acetylcysteine: A Synthesis of Two Decades of Evidence What Are NAD and NAC? MegaFood The neuroprotective effects of N acetylcysteine in psychiatric and neurodegenerative disorders: From modulation of glutamatergic transmission to restoration of synaptic plasticity ScienceDirect