GHK Cu is a naturally occurring tripeptide in human plasma. Levels average 200 ng ml at age 20 and drop to 80 ng ml by age 60 (Pickart et al., 2020). That decline tracks with GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack? PDF) The Effect of the Human Plasma Molecule GHK Cu on Stem Cell Actions and Expression of Relevant Genes 07 MARGOLINA c_04 LORD_c 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