Uses and Benefits #ghk GHK Cu is a naturally occurring peptide in human plasma that declines with age. When used in injections (usually subcutaneous), it can offer various benefits: Skin Rejuvenation and Anti Aging: OXITHION Reduced Sublingual L Glutathione 100mg (30s) DMD Skin Sciences New Advanced Sublingual Glutathione 1500mg Professional Grade Skin Whitening Single Vial You Look Light Canada GHK Cu is one of my personal favorites for a lot of reasons, but I can say without a doubt that it's use effectively stopped and reversed, my receiving hairline. However, there are