Search for copper peptides and stretch marks and you will find the claim stated with real confidence, usually with a study attached. Follow the citation trail and it narrows fast. There is one small human study that gets cited for this, it is more interesting than the confident version suggests, and it does not test what most articles imply it tests. Knowing the difference changes what you should expect from a serum.
This article covers GHK-Cu as a cosmetic ingredient. It is not medical advice, and nothing here has been evaluated by the FDA.
Key Takeaways
- The human evidence people cite is a 10-patient pilot study of a peri-procedural tripeptide/hexapeptide serum used alongside a 1540 nm nonablative fractional laser, not a trial of a standalone copper peptide cream [1].
- In that pilot, all patients reported subjective improvement, and adding the peptide serum increased objective improvement, reduced the incidence of post-inflammatory hyperpigmentation, and increased patient satisfaction [1].
- The published abstract calls the product a tripeptide/hexapeptide serum. It does not state that the tripeptide is GHK-Cu, so treating this as a GHK-Cu finding is an inference layered on top of the paper.
- No published trial has tested GHK-Cu by itself on striae distensae.
- There is a mechanistic reason to keep looking: GHK and GHK-Cu reduced IGF-2-driven TGF-beta1 secretion in cultured human dermal fibroblasts, which the authors connected to scar formation [2]. That is cell-culture work, not a striae result.
Why Stretch Marks Are a Hard Target for Any Topical
Striae distensae are not a surface pigment problem. They begin as a tearing and reorganisation of the dermis, the layer well beneath where most cosmetic ingredients comfortably reach, and they pass through stages. Early marks, striae rubrae, are reddish and still inflamed. Mature marks, striae albae, are pale, thinned, and structurally settled, with collagen and elastin arranged differently from surrounding skin.
That staging matters for reading any claim about them. A treatment that influences an active inflammatory and remodelling process has something to act on in a fresh mark. In a mature white stria, the process it would act on has largely finished. This is why energy-based devices, which deliberately create controlled injury to restart remodelling, feature in nearly every serious striae protocol, and why purely topical results in this area tend to be modest.
The Study People Are Actually Citing
The paper is a 2020 pilot study in Skinmed from a dermatology group at Thomas Jefferson University [1]. Ten patients received treatment with a 1540 nm nonablative fractional laser. The variable being tested was whether adding a tripeptide/hexapeptide serum around those laser sessions improved on the laser alone.
The reported outcome was positive on several fronts. Every patient reported subjective improvement. Adding the peptide serum increased objective improvement, increased patient satisfaction, and, in the detail that deserves more attention than it gets, reduced the incidence of post-inflammatory hyperpigmentation. That last point is a meaningful practical result, because post-inflammatory hyperpigmentation is one of the real risks of running energy devices on skin, particularly in deeper skin tones.
What the Study Does Not Establish
Four limits sit between this pilot and the claim that copper peptides fade stretch marks.
The first is the design. Ten patients, described by the authors as a pilot, is a study sized to justify a larger trial rather than to settle a question. There is no large controlled follow-up to point to.
The second is the intervention. The serum was used alongside a laser, as an adjunct. The study compared laser plus serum against laser, so it does not tell you what the serum does on stretch marks with no procedure involved. That is precisely the scenario most people are shopping for.
The third is the ingredient itself. The abstract names a tripeptide/hexapeptide serum and does not identify the tripeptide as GHK-Cu. Copper tripeptide is the tripeptide most people assume, and that assumption may well be right, but it is not something the published abstract states. Anyone citing this as a GHK-Cu study is adding an identification the source did not supply.
The fourth is scope. Even taken at its strongest, this is one pilot. GHK-Cu’s own literature is candid that topical delivery of the complex creates genuine formulation problems, which is a recurring theme across its cosmetic research [3], so extrapolating from one small combination-product study to a specific serum on your shelf is a long reach.
The Mechanistic Case, and Where It Stops
There is a coherent reason to be curious here rather than dismissive. Stretch marks involve disrupted dermal matrix, and GHK-Cu’s most-studied activity is matrix-related: collagen and elastin signalling, wound repair, and modulation of the genes involved in remodelling [4].
One specific finding lines up more directly. In cultured normal human dermal fibroblasts, IGF-2 was used to drive TGF-beta1 secretion, and GHK, GHK-Cu, and free copper ions each reduced that IGF-2-dependent secretion [2]. TGF-beta1 is central to fibrosis and scar formation, and the authors framed the result as relevant to preventing hypertrophic scarring.
Two things about that experiment keep it from carrying more weight than it should. It was cell culture at a single low concentration, not skin. And free copper chloride produced the same directional effect, so the result was not specific to the peptide complex. It is a reason to keep studying the ingredient. It is not evidence about stretch marks.
What This Means in Practice
If you are considering a copper peptide serum specifically for stretch marks, the honest position is that you would be buying ahead of the evidence. Nothing published shows GHK-Cu alone reducing striae, and the one human study in the neighbourhood tested a different thing, in a different configuration, in ten people.
The situation where the evidence is least of a stretch is the one the pilot actually studied: a peptide serum used around a procedure that is itself doing the structural work. If you are already having laser or microneedling treatment for striae, adding a peptide serum peri-procedurally is at least the scenario that was tested, and the reduced post-inflammatory hyperpigmentation finding is a reasonable secondary attraction. Aftercare decisions still belong with the clinician who ran the device, because the aftercare rules follow the specific device and settings rather than the ingredient.
For mature white stretch marks with no procedure involved, expectations should be low, and any product promising otherwise is running well past what has been published.
Frequently Asked Questions
Does GHK-Cu remove stretch marks?
No published study supports that. The closest human evidence is a 10-patient pilot in which a tripeptide/hexapeptide serum was used around laser sessions, not a trial of a copper peptide removing striae on its own [1].
Is there any human study of copper peptides on stretch marks?
There is one small pilot study of a combination peptide serum used as an adjunct to a 1540 nm nonablative fractional laser in 10 patients [1]. Its published abstract describes the product as a tripeptide/hexapeptide serum and does not state that the tripeptide is GHK-Cu, so reading it as a GHK-Cu result is an assumption rather than something the paper reports.
Would GHK-Cu work better on new stretch marks than old ones?
Nobody has tested that with GHK-Cu. The general pattern in striae treatment is that newer, still-inflamed marks respond better than mature white ones, because the mature stage involves settled structural change in the dermis rather than an active process. That is background about striae, not a finding about copper peptides.
Should I use GHK-Cu after laser or microneedling for stretch marks?
The pilot study used its peptide serum in exactly that peri-procedural role and reported added benefit over laser alone [1], which is the narrow situation the evidence actually speaks to. Any post-procedure product should be cleared with whoever performed the procedure first, since they set the aftercare rules for the specific device and settings used.
References
- McGuinn KP, Ross NA, Wang JV, Saedi N. Combination Tripeptide/Hexapeptide Serum With 1540 nm Nonablative Fractional Laser for the Treatment of Striae Distensae: A Pilot Study. Skinmed (2020). PMID 33397562
- Gruchlik A, Chodurek E, Dzierzewicz Z. Effect of Gly-His-Lys and Its Copper Complex on TGF-beta Secretion in Normal Human Dermal Fibroblasts. Acta Poloniae Pharmaceutica (2014). PMID 25745767
- Mortazavi SM, Mohammadi Vadoud SA, Moghimi HR. Topically Applied GHK as an Anti-Wrinkle Peptide: Advantages, Problems and Prospective. BioImpacts (2025). PMID 39963574
- Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. International Journal of Molecular Sciences (2018). PMID 29986520 (authors affiliated with Skin Biology, a company that sells copper-peptide products)
These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is for informational purposes only and is not a substitute for professional medical or dermatological advice. As an Amazon Associate we earn from qualifying purchases.
These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease. Content is for informational purposes only and is not medical advice; consult a qualified healthcare provider before starting any supplement. As an Amazon Associate we earn from qualifying purchases.
