Two very different uses. GHK-Cu is widely used topically in cosmetics (better-supported), and separately sold as an injectable research chemical (RUO, far less human data). This page is educational; it is not medical advice and not a use instruction.
What it is
GHK is a naturally occurring tripeptide (glycine-histidine-lysine) that avidly binds copper (Cu²⁺); the complex is written GHK-Cu. Levels of GHK in the body decline with age, which framed early interest in it as a repair signal.1
Proposed mechanism
Copper delivery & enzyme cofactor support — copper is required by enzymes involved in connective-tissue crosslinking.
Collagen / GAG stimulation — reported to promote synthesis of collagen, elastin, and glycosaminoglycans in skin models.1
Gene-expression modulation — in cell studies GHK-Cu is reported to shift the expression of a large number of genes toward a repair/anti-inflammatory profile.2
Read carefully: most robust data are topical / in-vitro. Systemic (injected) human evidence is limited — the leap from "resets genes in a dish" to "injected anti-aging" is exactly what Chapter 3 cautions against.
Evidence & status
Topical: reasonable cosmetic-science support for skin appearance.
Injectable/systemic: preclinical, minimal human; no Phase III.
Not an FDA-approved drug; the injectable form is sold RUO.
For educational and research purposes only. This content is not medical advice. Compounds referenced are research use only and not intended to diagnose, treat, cure, or prevent any disease. Free Peptide University does not sell compounds.