Cellular Glow Copper Peptide GHK Cu Serum for Face Frontiers Exploring the beneficial effects of GHK Cu on an experimental model of colitis and the underlying mechanisms 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK