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 Copper Peptide Benefits, Uses & Safety Intra V GHK Cu (Copper Peptide): A Smarter Way to Support Skin Regeneration Top Rated Scottsdale Med Spa Babyface A Dermatologist's Take on the Copper Peptide (GHK Cu) Trend OBM Geriatrics The Effect of the Human Plasma Molecule GHK Cu on Stem Cell Actions and Expression of Relevant Genes Copper Peptide (GHK Cu): Clinical Uses, Stability & Compounding Tips