Question: what is the difference between l-glutathione and reduced glutathione?
Answer: There are two different forms of glutathione: reduced glutathione (GSH, or L-glutathione), which is the active form, and oxidized glutathione (GSSG), the inactive state. As GSH patrols the cellular environment and puts out oxidative “free radical” fires, it becomes oxidized and inactive, thus turning into GSSG.