Primary Function: N-Acetyl-l-Cysteine (NAC) is a cellular antioxidant support that specifically promotes healthy lung tissue. N-Acetyl-l-Cysteine (NAC) is a free radical scavenger that supports glutathione levels in tissues. Supports cellular antioxidant defense system. Promotes healthy lung tissue. N-Acetyl-l-Cysteine (NAC) is a derivative of the dietary amino acid l-cysteine. NAC has a high affinity for lung tissue, which it supports through mucolytic and antioxidant action. By disrupting disulfide bonds, NAC thins mucus. It is a powerful free radical scavenger and thus supports the bodys natural defense system. NAC supports tissue levels of glutathione, a key component of the antioxidant defense system. It also has the ability to help chelate heavy metals.