N-acetyl cysteine (NAC) is a supplement form of cysteine, which is an amino acid found in high-protein foods. NAC has many health benefits, including replenishing antioxidants, detoxification of the liver and kidneys, improving symptoms of respiratory issues, and supporting immune health. It also plays a role in regulating glutamate levels in the brain, which may help improve brain health and benefit people with conditions such as Alzheimer's and Parkinson's diseases. NAC is also used to treat acetaminophen poisoning, and it has been studied for its potential effects on insulin resistance and mental health management