N-Acetyl Cysteine

NAC is a potent Antioxidant. 
NAC inhibits the carcinogens in Tobacco smoke.
NAC counteracts the excessive generation of Free Radicals in persons who Exercise:
NAC can lower Lipoprotein (a) levels by up to 70%.
NAC inhibits the oxidation of LDL Cholesterol.

NAC helps to maintain healthy Lung function, protects the Lungs from Free Radical damage and protects against the development of many ailments of the Lungs.

NAC (1,200 mg per day) helps to prevent Influenza infection, reduces the symptoms of existing Influenza infection and reduces the duration of Influenza infections (especially in elderly and chronically ill people).

N-Acetyl Cysteine (NAC) (1,800 mg per day) is presently undergoing clinical trials as an enhancer of the Immune System in persons with Acquired Immune Deficiency Syndrome (AIDS) and as a possible means of preventing HIV developing into full-blown AIDS [research to date shows that supplemental NAC can restore Cysteine and Glutathione levels and (significantly) inhibit the replication of the HIV virus].

NAC reduces the toxic side effects of Cyclophosphamide (a Pharmaceutical Drug used to treat some cases of Cancer).

NAC prevents the Liver damage that leads to death after Paracetamol overdose (to be effective NAC must be administered within 12 hours of Paracetamol poisoning (due to NAC stimulating Glutathione production which functions as an Antioxidant and protects the Liver from Paracetamol -induced oxidative damage) [research - this attribute of NAC is well-proven and NAC is now the standard treatment for Paracetamol poisoning].

NAC has been suggested as a viable alternative to Protease Inhibitors for the treatment of AIDS as NAC is an effective Protease Inhibitor.
NAC protects the body's endogenous Protease Inhibitor Protein (Alpha-1 Antitrypsin) by preventing the oxidation of Methionine residues within this Protein.

NAC helps to prevent various types of Cancer [NAC exerts antimutagenic effects against a wide variety of mutagenic chemicals]:

NAC enhances the effectiveness of Interferon Alpha in the treatment of Hepatitis C (primarily by counteracting the depletion of Glutathione).

NAC raises intracellular Cysteine levels (this intracellular Cysteine is then incorporated into Glutathione).
NAC prevents the destruction of Glutathione (by preventing the oxidation of Glutathione).

NAC enhances the effectiveness of Interferon Alpha in the treatment of Hepatitis C.
NAC inhibits the proliferation of Streptococcus pneumoniae (especially in the bronchial tissue of Smokers with chronic Bronchitis).

NAC facilitates the excretion of Arsenic from the body [affected by chronic Arsenic poisoning have been saved from death when administered NAC upon arrival at hospital].
NAC counteracts the toxic effects of Mercury and helps to remove (chelate) Mercury from the body.