Your cells contain glutathione, which is a substance made from three amino acids: cysteine, glutamate, and glycine. Glutathione acts as an important antioxidant in your body. That means it helps combat free radicals. These are molecules that can damage your body's cells. Glutathione plays a role in many chemical reactions in your body. It also helps detoxify chemicals, including some that your body creates naturally, as well as pollutants and drugs. Your supply of glutathione seems to decrease as you get older, possibly because your body can't create as much. Lower glutathione levels appear to go hand-in-hand with poorer health. For instance, lower levels may play a role in many conditions that are more likely to develop in older people.