GHK Cu: The Peptide That Supports Healthy Aging GHK Cu (copper peptide) is naturally occurring in the body and plays a role in supporting skin health, collagen production, and tissue repair. As Say hello to your skin's new BFF GHK Cu is a powerful peptide that supports collagen production, speeds healing, improves hair growth, and helps fight visible signs of aging. This tiny molecule GHK Cu Peptide for Hair Growth: Science, Benefits, and How It Works Time for a little GHK CU update for the people who are interested. Its day 9. I took a little break on day 5 just so my body didnt get too used to the peptides and Ill just keep going in this 5