By age 30, your skin produces about 25% less collagen. By 40, that number can reach 40%. This decline affects more than just how your skin looks. It changes how it heals, GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack? Relief of ovalbumin induced airway remodeling by the glycyl l histidyl l lysine Cu2+ tripeptide complex via activation of SIRT1 in airway epithelial cells ScienceDirect Resetting Skin Genome Back to Health Naturally with GHK Springer Nature Link Intermediate Cu(II) Thiolate Species in the Reduction of Cu(II)GHK by Glutathione: A Handy Chelate for Biological Cu(II) Reduction Inorganic Chemistry