Quick answer: most GHK-Cu before and after claims come from social media photos, not trials. The human trials that exist are small: a few company-linked 12-week cream studies in women reported fewer fine lines and firmer, thicker skin, but they were never published as full peer-reviewed papers.[1] The one published randomized facial trial found no measurable difference in wrinkles or redness, only higher patient satisfaction.[2] There are no published human studies of GHK-Cu injections for skin.
This page lays out what each study measured, so you can compare real results with the photos. For the wider picture, see our GHK-Cu profile, the GHK-Cu research summary and the healing peptides hub.
Why trial measurements beat photos
A trial’s “before and after” is a set of measurements taken the same way at the start and the end, ideally compared with a placebo cream. Researchers use standardized photos, ultrasound to measure skin thickness, skin biopsies for collagen and validated questionnaires.
Online photos lack all of that. Lighting, angle, makeup, hydration, filters and other treatments used at the same time can all change how skin looks. A 2023 analysis of YouTube videos about copper peptides was titled after its main finding: unsubstantiated claims about their uses in dermatology.[9]
The 12-week GHK-Cu cream studies
The most-quoted GHK-Cu results come from studies summarized in a 2015 review written by GHK’s discoverer and colleagues at a skincare company.[1]
| Study (as described in the review) | Who | Length | What was reported |
|---|---|---|---|
| Thigh collagen study | Women | 1 month | Collagen rose in 70% with GHK-Cu, vs 50% with vitamin C cream and 40% with retinoic acid |
| Facial cream | 71 women with mild to advanced sun damage | 12 weeks | Better laxity, clarity and appearance; fewer fine lines; shallower wrinkles; denser, thicker skin |
| Eye cream | 41 women | 12 weeks | Fewer lines and wrinkles than placebo or a vitamin K eye cream |
| Facial cream, twice daily | 67 women aged 50 to 59 | 12 weeks | Firmer, clearer skin; fewer fine lines, coarse wrinkles and blotchy pigment |
Source: Pickart and colleagues, 2015.[1]
A 2026 systematic review found that about 35% of the GHK-Cu research it included had the discoverer or a colleague from the same company as an author, which limits independent confirmation.[4]
The one published randomized facial trial
The clearest published test is a 2006 trial in people who had laser resurfacing around the mouth.[2] Patients were randomly assigned to aftercare with or without GHK-Cu products.
- Who finished: 13 patients.
- Before and after measures: redness tracked by computer analysis and by evaluators who did not know which group patients were in; wrinkles and overall skin appearance at 12 weeks; a validated questionnaire.
- Results: everyone’s wrinkles and skin quality improved after the laser, but there was no difference between groups. Redness did not clear faster with GHK-Cu.
- The one positive: patients using GHK-Cu rated their overall skin improvement higher on the questionnaire.
In other words, the people using GHK-Cu felt better about their skin, but the objective measurements could not tell the groups apart.
Newer GHK-Cu skin studies
- Combination cream (China, 2026): a face cream combining GHK-Cu with a ferment extract reduced wrinkles and improved skin barrier measures in a clinical test.[6] Because GHK-Cu was not tested alone in that clinical study, its own contribution cannot be separated.
- Eyebrows (Thailand, 2026): in a randomized, double-blind, split-face trial, 18 adults applied 2% GHK-Cu serum to one brow and a placebo serum to the other, twice daily for 12 weeks. Hair count and thickness increased on the treated side, with no serious side effects or allergic reactions.[7] See copper peptides for hair.
What reviews conclude
- A 2025 review found GHK clearly active in cell studies but noted a “surprising absence” of clinical studies for wrinkles.[3]
- A 2026 systematic review in aesthetic medicine included 20 studies, of which only 2 were randomized trials, and called for larger, controlled trials.[5]
- Another 2026 review said most randomized trials are small facial cream studies, and none has tested GHK-Cu with microneedling in an adequately powered human trial.[4]
GHK-Cu injection before and after
Injected GHK-Cu has become popular, and so have injection before-and-after photos. There is no published human trial behind them. A 2026 sports medicine review found no clinical data supporting injected GHK-Cu for musculoskeletal problems,[11] and FDA says compounded injectable GHK-Cu may pose a risk of immune reactions because of clumping and impurities, with limited human data.[10] Our topical vs injectable peptides for skin guide compares the two routes.
Wounds: a negative result
GHK-Cu is often marketed for healing, but in a 1992 randomized trial in 86 people with venous leg ulcers, a 0.4% copper tripeptide cream did no better than placebo. Only the comparison cream, silver sulfadiazine, shrank ulcers more than placebo.[8] See best peptides for wound healing.
How to judge a GHK-Cu before and after photo
- Same lighting, angle and distance in both photos?
- No makeup, filters or retouching?
- What else was used: retinoids, sunscreen, lasers, fillers?
- How long between photos, and is the “after” the best day or a typical one?
- Was the product a cream or an injection, and from where?
If several answers are unknown, treat the photo as an advertisement rather than evidence.
It also helps to remember what the trials could detect. In the laser study, every patient improved over 12 weeks whether or not they used GHK-Cu, because skin heals after resurfacing on its own.[2] Many before-and-after posts are taken during a period when skin would improve anyway: after a procedure, after stopping a harsh product, or after starting sunscreen. Only a comparison group can separate the effect of the copper peptide from everything else.
Questions to ask a dermatologist
- Is a GHK-Cu product likely to add anything to my current routine?
- Would a better-studied option, such as a retinoid, suit my skin?
- Is it safe with the other products or procedures I use?
For product use, see how to use copper peptides, copper peptides vs retinol and GHK-Cu vs Matrixyl.
