N-acetylcysteine (NAC) is an essential amino acid for the formation of proteins and glutathione in the body. This Now Foods supplement contains 600mg of NAC, as well as molybdenum and selenium, which are important trace elements with various functions. Selenium contributes to the protection of cells and the maintenance of normal hair and nails, while molybdenum is essential for the metabolism of sulfur-containing amino acids. Now Foods NAC capsules are high quality, tested for quality and purity in independent laboratories. Additionally, they are free from gluten and genetic engineering. Consult a doctor or alternative health professional for individual consumption recommendations.