What it is

Glutathione, GSH, is a tripeptide: gamma-glutamyl-cysteinyl-glycine. Every cell makes it in two steps, and the first step, run by glutamate-cysteine ligase, is limited by how much cysteine is available. The liver makes the most and exports it to the rest of the body. Levels fall with age, with chronic illness, with alcohol and with toxin load.