GHK-Cu for Skin: The Copper Peptide
GHK-Cu is the most documented peptide in the skin conversation. It is a small copper-bound tripeptide that occurs naturally in the body, where its level falls with age.
This deep-dive explains what it is, how it is associated with skin and collagen, what evidence exists, and the practical quirks (like the blue colour).
On this page
What GHK-Cu is
GHK-Cu is the copper(II) complex of the tripeptide glycyl-L-histidyl-L-lysine. The sequence occurs in human plasma and binds copper tightly. Plasma levels are higher in youth and decline with age, which is part of why it is framed as a "restorative" skin compound.
How it is associated with skin
In laboratory work GHK-Cu is linked with two things at once: building new collagen and other matrix components, and clearing damaged matrix — a dual action most single ingredients do not have. It is also associated with antioxidant gene activity. Together these are why it is such a persistent collagen and skin-structure topic.
What the evidence shows
GHK-Cu has decades of cosmetic and wound-healing literature and smaller human studies (e.g. on wrinkle depth and skin density), usually under 50 subjects per arm. There is no large multi-centre trial. The evidence is stronger than for many newer peptides but still limited — treat it as promising, not proven.
Reference and reconstitution
See the GHK-Cu product page for its reference protocol and the calculator for the maths. GHK-Cu is also the anchor of the KLOW blend.
Frequently asked questions
Why is GHK-Cu blue?
The blue comes from the copper(II) ion held in the tripeptide complex — it is a normal characteristic of authentic GHK-Cu, not contamination.
Is GHK-Cu used topically or reconstituted?
Both appear in references — it is used in topical cosmetic formulations and also reconstituted for research. The product here is supplied for laboratory research use only.