Glutathione is a sulfhydryl (-SH) antioxidant, antitoxin, and enzyme cofactor. It is found in the vast majority of prokaryotic and eukaryotic cells, where it often represents the major pool of non-protein reduced sulphur. It cannot enter most cells directly and therefore must be made available inside the cell from its three constituent amino acids: Glycine, Glutamate and Cysteine. The rate at which Glutathione can be made depends on the availability of Cysteine, which is relatively scarce in foodstuffs. Furthermore, the Cysteine...