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Skin & Cosmetic Preliminary evidence

AHK-CU

AHK-Cu (Alanine-Histidine-Lysine copper complex)

Also known as: AHK-Cu, AHK copper peptide

Written and reviewed by the Peptide.it editorial team Last reviewed June 2026 · Every claim is tier-rated and sourced

In plain language

AHK-CU is a copper-bound tripeptide used in cosmetic products, sometimes marketed for hair and scalp as well as skin. It is promoted to support a healthier appearance through copper delivery and peptide signaling. Most supporting data is in-vitro or manufacturer-sponsored, so independent human evidence is sparse.

What it is explored for

AHK-CU is a copper tripeptide with an appealing cosmetic rationale, pairing copper delivery with peptide signaling for skin, scalp, and hair appearance. Being candid, most supporting data is in-vitro or manufacturer-sponsored, so independent human evidence is sparse and the benefits are best treated as preliminary. Here is where cosmetic interest is focused.

  • Skin appearance and tone
  • Scalp and hair-care formulas
  • Copper delivery to skin
  • Matrix and collagen-support research
  • Cosmetic anti-aging interest

These are areas of active interest and reported use, not proven outcomes. This peptide carries a preliminary evidence rating, see the evidence summary below for how strong the science actually is.

How it works

AHK-CU pairs the AHK tripeptide with copper. The rationale combines the role of copper as a cofactor in skin and the proposed signaling of the peptide.

  • Copper delivery. Copper is a cofactor for enzymes involved in matrix formation, and copper peptides are marketed as a way to deliver it to skin or scalp.
  • Signal peptide rationale. The AHK sequence is promoted as a signal associated with matrix and follicle support, including in hair-focused products.
  • Combination use. It is frequently used within blended formulas, which makes its individual contribution difficult to isolate.

The proposed mechanisms come largely from in-vitro work and manufacturer rationale rather than robust human in-vivo data.

Evidence summary

Independent human evidence for AHK-CU is sparse. Most support comes from cell-culture work and manufacturer materials, including hair-related claims that are not well established. Benefits should be regarded as preliminary.

Reported safety & side effects

AHK-CU is generally considered well tolerated in leave-on cosmetics at typical use levels. As with other copper peptides, formulation and pairing with certain actives can matter. Independent safety data are sparse.

Typical reactionsGenerally well tolerated; irritation uncommon
Use contextTopical cosmetics for skin
Human safety dataSparse independent data; not an approved drug

Frequently asked

Is AHK-CU the same as GHK-Cu?

No. Both are copper tripeptides, but they use different amino acid sequences (AHK versus GHK) and are marketed for somewhat different uses.

Does it regrow hair?

There is no strong independent evidence for that. Hair-related claims rest largely on in-vitro work and manufacturer materials and should be considered preliminary.