Peptide Footnotes

The claim

The copper peptide GHK-Cu rebuilds aged skin
Mixed

Some real evidence, with clear limits or conflicts.

Evidence strength2/5

Is GHK-Cu Really a Skin Rejuvenator?

Filed 23 Oct 2026 · Last reviewed · 1 min read · 4 reads

A copper-binding tripeptide with a loyal following. Lab and small cosmetic studies look encouraging, but strong human trials are scarce.

What it is

GHK is a three-residue peptide (glycine, histidine, lysine) that binds copper. It occurs naturally in blood and falls with age, which is the origin of many "restore your levels" stories.

What the evidence shows

Cell and animal studies show effects on collagen production and wound repair. Human data come mostly from small cosmetic studies, often unblinded or comparing a cream with nothing.

Open questions

  • Does enough peptide cross the outer skin layer to matter?
  • Which effect comes from the peptide and which from the copper?
  • How does it compare with proven topical ingredients?
Promising lab biology is where a claim starts, not where it ends.

Verdict

Mixed, leaning weak. Plausible and low-risk in a cream, but the dramatic claims run far ahead of the trials.

Bottom line

  • Cosmetic use is a different matter from injections sold online.
  • Injectable products are not approved cosmetics.
  • Ask for controlled human data, not testimonials.

Educational only. Not medical advice. See the disclaimer.

Neighbouring files

No. 38Skin & Beauty Weak Peptide eye creams visibly remove under-eye wrinkles Are Peptide Eye Creams Worth the Price? 2/51 min read No. 27Skin & Beauty Mixed Collagen drinks reduce wrinkles and improve elasticity Do Collagen Peptides Really Smooth Skin? 3/51 min read No. 22Skin & Beauty Unproven A proven GHK Cu dose exists for injection GHK Cu Dosage Claims Checked From Cream Trials to Injection Gaps 1/56 min read