What is NAC? NAC (N-Acetyl-Cysteine) is an altered form of the amino acid cysteine, which is commonly found in most high-protein foods. However, unlike cysteine, NAC is not found in the diet and therefore must be supplemented. NAC boosts cellular antioxidant protection through its ability to raise body levels of glutathione, one of the bodys most important and valuable antioxidants.* NAC, a free radical defender, is a necessary component of the bodys defense system. Healthy Lungs - Protects lung tissue and overall respiratory function.* Healthy Heart - Reduces homocysteine levels and improves blood flow.* Healthy Liver - Best remedy to prevent liver damage caused by high doses of acetaminophen, the common over-the-counter pain reliever .** These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.