Defy GHK Cu (glycyl L histidyl L lysine) is a naturally occurring copper binding peptide found in human plasma. As levels decline with age, so may its support of the biological processes involved in collagen production, skin Amazon.com: Copper Peptides Serum for Face Peptides Collagen Renewal & Anti Aging Serum GHK Cu, EGF, Hyaluronic Acid,Collagen Anti Wrinkle, Firming, Moisturizing Korean Skin Care,25mL 0.88 Fl Oz : Beauty & Personal Care GHK Cu Peptide The benefits, side effects, and more [2026] GHK Cu, commonly known as copper peptides, are found naturally within the human body where they play a vital role in skin repair and maintenance. Copper peptides support optimal skin function by helping