NAC (N-Acetyl-L-Cysteine) is known as a mucolytic agent, which means it helps clear mucus from the lungs. NAC is also a precursor to glutathione, a vital antioxidant for immune, liver, and brain health. Glutathione helps scavenge free radicals, which occur naturally due to chemical processes in the body but can also build up due to exposure to toxins or pollution. NAC is ideal for those who want to protect against oxidative stress caused by respiratory conditions.