N-Acetyl-L-Cysteine (or simply NAC) doesn’t exactly roll off the tongue, but it is a potent nutrient and free-radical scavenger that does wonders for your whole-body health. It’s particularly beneficial to respiratory, liver and immune support. NAC is a precursor to glutathione, another powerful antioxidant that protects your cells and high-performing organs like your liver. Life Extension’s N-Acetyl-L-Cysteine (NAC supplement) is a daily nutritional supplement that is formulated to deliver 600 mg of this potent, rapidly absorbed, all-star nutrient.