Frontiers Exploring the beneficial effects of GHK Cu on an experimental model of colitis and the underlying mechanisms GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack? Unlocking the Secrets of GHK Cu: The Revolutionary Peptide for Youthfu GHK Cu (Copper Peptide) is a naturally occurring peptide in the body that binds with copper to support cell repair and renewal. As we age, our levels decrease and thats where supplementation or