Copper Peptides for Skin: What GHK Cu Does and How It Compares to Retinol Peptides Injectable Peptides for Anti Aging? A Dermatologist Explains GHK Cu YouTube Absence of evidence isnt evidence of absence its a popular argument, but its not how we should be guiding treatment decisions. In this short, I respond to a comment about GHK Cu injections for Ever heard of GHK Cu peptide? It's a naturally occurring copper peptide that helps repair tissue, stimulate collagen, and support skin healing. When used in injectable form, it works at a deeper level