Glow from within with GHK Cu Copper Peptide , This powerhouse peptide supports collagen production, skin repair, and hair follicle health, helping improve skin firmness, radiance, and support GHK Cu: The Peptide That Supports Healthy Aging GHK Cu (copper peptide) is naturally occurring in the body and plays a role in supporting skin health, collagen production, and tissue repair. As GHK Copper Peptides for Skin and Hair Defy Medical GHK Cu Copper Peptide for Hair Loss: Results, Mechanism, and What to Expect