[DOI] [Google Scholar] Oblak M, Randic M, Solmajer T
It acts through ghrelin-like GHSR signaling but is not a peptide
They are sold in the form of pills, capsules or wafers
Pigmentation Disorders and Melanogenesis Regulation GHK-Cu influences melanogenesis through complex, concentration-dependent mechanisms with potential applications in both hyperpigmentation and hypopigmentation disorders
Most food supplement manufacturers dont do this and there is no requirement in the industry to actually test
(8) Loren Pickart, Jessica Michelle Vasquez-Soltero, and Anna Margolina (2012) The Human Tripeptide GHK-Cu in Prevention of Oxidative Stress and Degenerative Conditions of Aging: Implications for Cognitive Health Oxidative Medicine Cellular Longevity, 2012 May 10, Volume 2012, Page 324832