I was super skeptical because I've literally tried everything Retinol destroyed my skin. Vitamin C oxidized and stung. Four different peptide serums and nothing actually worked. Then I tried GHK Cu. 6 weeks Amazon.com: ANAI RUI Copper Peptides Serum for Face Ghk Cu Peptide Serum + Hyaluronic Acid Reduces Fine Lines & Wrinkles, Plumping and Radiant Skin, 1.fl.Oz : Beauty & Personal Care Amazon.com: Skin Perfection Copper Peptide Serum GHK CU 1% for Face & Hair Copper Peptides for Skin, Hair, & Scalp 1% Blue Liquid for Face, Neck, Body, Scalp Multi Use Serum Booster with Pptido de cobre GHK GHK Cu Tripptido 1 Copper Peptide (GHK Cu) 2% Recovery Serum Copper Peptides for Skin: What GHK Cu Does and How It Compares to Retinol