Peptides/Skin and hair
GHK-Cu
Also sold as Copper peptide, Copper tripeptide-1
The blue copper peptide in serums. One of the few skincare peptides with real human studies behind the firmness and fine-line claims.
At a glance
What people use it for
- Fine lines and skin firmness
- Improving skin texture and tone
- Supporting wound healing
- Hair thickness, in some formulations
How it is taken
Applied to the skin in a serum or cream, typically at 1% to 2%. Also sold for injection, which is neither necessary nor advisable.
Evidence
Mixed human evidence
Good to know
- Irritation and redness, especially when layered with strong acids or retinoids
- Copper can discolour the product and occasionally the skin
- Injectable versions carry all the risks of unregulated injectables for no added benefit
GHK-Cu is three amino acids holding a copper atom, and it turns skincare products a distinctive blue. It occurs naturally in human blood plasma, and levels fall with age, which is the origin of the anti-ageing pitch.
What people use it for
Firmness and fine lines, mostly. It is one of the more popular actives in serums aimed at skin that has started to lose bounce. Some people use it as a gentler alternative to retinol, since it does not cause the same peeling.
It also turns up in hair products aimed at thickness.
What the evidence shows
Better than most of this category. Small human studies of GHK-Cu creams have reported improvements in skin density, firmness and fine lines over several weeks, and it has been studied for wound healing since the 1970s. The trials are small and often industry-funded, but they exist and they are in people.
The mechanism is reasonably well described: it appears to stimulate collagen production and has antioxidant activity.
What to know before
Two practical points. GHK-Cu does not play well with strong acids or high-strength vitamin C in the same routine, so most people alternate them rather than layering. And concentration matters; a product with copper peptides sixteenth on the ingredient list is a colour choice, not an active dose.
Injectable GHK-Cu is sold online. There is no good reason for it. This is a compound whose entire evidence base is topical, and injecting an unregulated product to achieve a result a cream already achieves is a poor trade.
Last reviewed .