glutathione role in skin whitening works for by reducing melanin production, which helps lighten the skin and reduce pigmentation. It acts as an antioxidant, protecting the skin from oxidative damage, which can cause aging and Glutathione Injections For Skin Whitening:
Description
In one study, both GSH and GSSG achieved a skin lightening effect though it takes a few weeks to develop

Cell Reports, 41(4), 111532

H.PathamB.TabatabaiL.KansaraA

Epitalon is often described as a longevity peptide because researchers are investigating its potential effects on cellular aging rather than treating a specific medical condition
