Does GHK Cu Really Work? 40 Years of Research Reviewed 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 Molecular crystal structure of the tripeptide GHK Cu. In solution, Download Scientific Diagram GHK CU is one of the most underrated anti aging peptides and it's been around longer than almost everything else. In my experience, GHK CU isn't just a cosmetic peptide. It improves collagen remodeling, reduces GHK Cu (Copper Peptide): A Smarter Way to Support Skin Regeneration Top Rated Scottsdale Med Spa Babyface Effects of Copper Tripeptide on the Growth and Expression of Growth Factors by Normal and Irradiated Fibroblasts Jeffrey D. Pollard, Susan Quan, Thomas Kang, R. James Koch, 2005