NAC ou glutathion : lequel prendre ? 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 is the body's master antioxidant. It is important for handling oxidative stress, detoxification, and immune health. Low glutathione is linked to many chronic illnesses. Knowing what your body needs to make L Glutathione VS NAC: Differences, Similarities, and Uses