Glutathione it is produced in the liver and plays an important role in the Metabolism. It is composed of cysteine ( is one of three gluathione precusors your body needs to make glutahtione. The other two are Glyceine and Glutamic Acid.
Your body makes cysteine mainly from methionine. Other precursors ( building blocks ) for cysteine are the minerals: Selenium and folate and the B vitamins: B1, B2, B6, B12.
If you are deficient in any of the above nutrients ( or they are being used in other bodily functions) your body cannot make cysteine and thus cannot make glutahtione.
A simple solution is to take N-Acetyl-Cysteine (NAC). Once NAC is absorbed into your body it is easily and quickly converted into cysteine, which is then used by your body to manufacture glutathione.
An excellent supplement that contains the most beneficial and safe amounts of NAC a long with the perfect combination of Vitamin C is MaxGXL.
MaxGXL contains other ingredients, as well, that support and work syneristically with NAC to help the body manufacture more cysteine and in trun more glutahtione.