Goal
Best-studied peptides for skin & hair
Ranked by the strongest evidence rung each compound holds, with what the study measured beside it. 33 were checked; 9 produced a graded row.
Last updated
33 compounds were read against these 7 conditions; 9 produced a graded row. The other 24 are named further down.
About this page's scope
Two of these seven conditions — skin laxity and skin dryness — have a list of compounds checked and no graded row at all. That is not a gap in this page; it is the clearest thing on it.
The ranking, and the key it uses
Ordered by the best rung the compound holds anywhere in this goal; then by what that study measured; then by how many graded rows it holds here, as a tie-break only; then by name. There is no blended score — one number mixing the rung and what was measured would invent a third scale nothing was graded against. Every rung links to the rubric that assigned it.
Reading the strip
1 human RCT2 human observational3 human case series4 animal in vivo5 in vitro6 theoretical7 computational
A filled cell means at least one graded row at that rung. Its colour is what the strongest such study measured: direct outcome · surrogate marker · mechanistic only. An outlined cell means no row at that rung.
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Palmitoyl Pentapeptide-4 (Matrixyl)
human RCT · direct outcome · 3 graded rows across 3 of 7 conditions
3 graded rows, 1 source
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Skin ageing
human RCT Direct outcome Not approved for this condition
- Who was studied
- Caucasian women aged 35-55, n=93, topical (3 ppm pal-KTTKS in a moisturiser), 12 weeks, split-face left-right randomised
A 12-week double-blind, split-face, randomised comparison of a moisturiser with and without 3 ppm palmitoyl pentapeptide-4 measured wrinkles and fine lines by image analysis and expert grading, and reported improvement versus the placebo side. It is a single cosmetic-industry trial in one narrow population; no independent replication is on file, and the peptide is a cosmetic ingredient with no regulatory approval for any skin condition.
Source DOI 1 primary source read for this row
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Photoageing
human RCT Direct outcome Not approved for this condition
- Who was studied
- Caucasian women aged 35-55 with photoaged facial skin, n=93, topical (3 ppm pal-KTTKS in a moisturiser), 12 weeks, split-face left-right randomised
The enrolled population was photoaged facial skin specifically: a 12-week double-blind, split-face, randomised comparison of a moisturiser with and without 3 ppm palmitoyl pentapeptide-4 measured wrinkles and fine lines in photodamaged skin by image analysis and expert grading, and reported improvement versus the placebo side. It is a single cosmetic-industry trial with no independent replication on file, and the peptide has no regulatory approval for any skin condition.
Source DOI 1 primary source read for this row
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Facial wrinkles
human RCT Direct outcome Not approved for this condition
- Who was studied
- Caucasian women aged 35-55, n=93, topical (3 ppm pal-KTTKS in a moisturiser), 12 weeks, split-face left-right randomised
A 12-week double-blind, split-face, randomised comparison of a moisturiser with and without 3 ppm palmitoyl pentapeptide-4 measured facial wrinkles and fine lines directly, by quantitative image analysis and expert grading, and reported improvement versus the placebo side. It is a single cosmetic-industry trial in one narrow population; no independent replication is on file, and the peptide has no regulatory approval for any skin condition.
Source DOI 1 primary source read for this row
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Decapeptide-12
human RCT · direct outcome · 2 graded rows across 2 of 7 conditions
2 graded rows, 1 source
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Hyperpigmentation
human RCT Direct outcome Not approved for this condition
- Who was studied
- women with Fitzpatrick phototype IV and moderate recalcitrant melasma, n=5, 16 weeks
A split-face, randomised, double-blind, vehicle-controlled pilot applied 0.01% decapeptide-12 twice daily and graded melasma appearance on a 10-point scale, reporting improvement on the treated side in all five participants. The diagnosis studied was melasma specifically, not post-inflammatory hyperpigmentation, and n=5 with an investigator grading scale rather than MASI or colorimetry is the whole human controlled record. The larger decapeptide-12 studies on file are open-label and combine the peptide with 20% glycolic acid and sunscreen, so they cannot attribute any pigment change to the peptide.
Source PubMed 4 primary sources read for this row
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Melasma
human RCT Direct outcome Not approved for this condition
- Who was studied
- women with Fitzpatrick phototype IV and moderate recalcitrant melasma, n=5, 16 weeks
A split-face, randomised, double-blind, vehicle-controlled pilot applied 0.01% decapeptide-12 twice daily to diagnosed melasma and graded its appearance on a 10-point investigator scale, reporting improvement on the treated side in all five participants. n=5 with an investigator scale rather than MASI or colorimetry is the entire controlled human melasma record for this peptide. The larger decapeptide-12 studies on file are open-label and combine the peptide with 20% glycolic acid and sunscreen, so they cannot attribute any pigment change to the peptide.
Source PubMed 4 primary sources read for this row
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Hexapeptide-9
human RCT · direct outcome · 2 graded rows across 2 of 7 conditions
2 graded rows, 1 source
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Skin ageing
human RCT Direct outcome Not approved for this condition
- Who was studied
- adult men and women with ageing skin, n not reported in the abstract; topical 0.002% serum twice daily, 56 days
A randomised, double-blind, vehicle- and active-controlled 56-day trial of a topical 0.002% cyclized hexapeptide-9 serum measured crow's feet and forehead wrinkle number, area and roughness against a 0.002% retinol serum and vehicle, and reported larger reductions than retinol on all measured outcomes except crow's feet roughness. The tested material is a cyclized variant, not plain hexapeptide-9, and the enrolled number was not reported in the abstract.
Source DOI 1 primary source read for this row
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Facial wrinkles
human RCT Direct outcome Not approved for this condition
- Who was studied
- adult men and women with ageing skin, n not reported in the abstract; topical 0.002% serum twice daily, 56 days
A randomised, double-blind, vehicle- and active-controlled 56-day trial of a topical 0.002% cyclized hexapeptide-9 serum measured crow's feet and forehead wrinkle number, area and roughness against a 0.002% retinol serum and vehicle, and reported larger reductions than retinol on all measured wrinkle outcomes except crow's feet roughness. The tested material is a cyclized variant, not plain hexapeptide-9, and the enrolled number was not reported in the abstract.
Source DOI 1 primary source read for this row
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1 graded row, 1 source
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Skin ageing
human RCT Direct outcome Not approved for this condition
- Who was studied
- healthy adults, both sexes, n=70, oral 1,650 mg/day low-molecular-weight collagen peptide, 8 weeks plus 2-week washout
A randomised, double-blind, placebo-controlled trial of an oral collagen peptide measured facial wrinkle depth, height and visual severity, elasticity (R2/R5/R7), hydration and dermal density, and reported improvement against placebo. A 2026 systematic review and meta-analysis of 19 randomised trials (n=1,341) found only a modest pooled wrinkle effect, driven by oral rather than topical peptides. This is oral exposure only; nothing here supports a topical collagen peptide product.
Source PubMed 2 primary sources read for this row
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Tetrapeptide-30
human RCT · direct outcome · 1 graded row across 1 of 7 conditions
1 graded row, 1 source
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Hyperpigmentation
human RCT Direct outcome Not approved for this condition
- Who was studied
- women with Fitzpatrick skin types V-VI in South Africa, 12 weeks; enrolled number not reported in the source abstract
A double-blind, vehicle-controlled study of a PKEK (tetrapeptide-30) formulation used expert grading of standardised digital images and reported the peptide formulation superior to vehicle on overall appearance and evenness of skin tone at 12 weeks; the abstract does not state the randomisation method or the number enrolled. The population was general uneven facial pigmentation in deeply pigmented skin, not a melasma diagnosis. A separate Experimental Dermatology paper reports four vehicle-controlled human studies, but its measured pigment-spot fading comes from PKEK combined with sodium ascorbyl phosphate, so that reduction is not attributable to the peptide alone.
Source DOI 2 primary sources read for this row
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Argireline (Acetyl Hexapeptide-3)
human observational · direct outcome · 2 graded rows across 2 of 7 conditions
2 graded rows, 1 source
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Skin ageing
human observational Direct outcome Not approved for this condition
- Who was studied
- adult women, n=19, topical hyaluronic acid serum with and without Argireline applied to opposite sides of the face, 4 weeks
A double-blind, within-subject split-face study measured facial wrinkle scores by Visia imaging after 4 weeks and found no statistically significant reduction on the Argireline side. Randomisation of side allocation was not reported, so this is graded below human_rct despite the vehicle control. This is the only controlled human wrinkle study of Argireline alone located; every other human study of it is a multi-ingredient formulation from which the peptide's own contribution cannot be separated.
Source PubMed 1 primary source read for this row
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Facial wrinkles
human observational Direct outcome Not approved for this condition
- Who was studied
- adult women, n=19, topical hyaluronic acid serum with and without Argireline applied to opposite sides of the face, 4 weeks
A double-blind, within-subject split-face study measured facial wrinkle scores by Visia imaging after 4 weeks and found no statistically significant wrinkle reduction on the Argireline side. Randomisation of side allocation was not reported, so this is graded below human_rct despite the vehicle control. It is the only controlled human wrinkle study of Argireline alone on file; every other human study of it is a multi-ingredient formulation from which the peptide's own contribution cannot be separated.
Source PubMed 1 primary source read for this row
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1 graded row, 1 source
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Facial wrinkles
human observational Direct outcome Not approved for this condition
- Who was studied
- 24 healthy adults, dissolving microneedle patch containing acetyl octapeptide-3 with L-ascorbic acid 2-glucoside and cyclic lysophosphatidic acid on a hyaluronic acid backbone, applied overnight to one periorbital side against a hyaluronic-acid-only placebo patch on the other, assessed over 28 days
The only human trial with a wrinkle outcome tested the peptide inside a four-ingredient patch against a hyaluronic-acid-only placebo, and reported improved eye wrinkles, elasticity and trans-epidermal water loss on the treated side. It is a single manufacturer-run study of 24 subjects, and the design cannot say which ingredient did the work. No trial of acetyl octapeptide-3 on its own has ever measured a wrinkle. Rung set by review: twenty-four adults with the placebo patch on the other side of the same face; controlled, manufacturer-run, and never described as randomised.
Source PubMed 7 primary sources read for this row
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Nonapeptide-1
in vitro · mechanistic only · 2 graded rows across 2 of 7 conditions
2 graded rows, 1 source
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Hyperpigmentation
in vitro Mechanistic only Not approved for this condition
- Who was studied
- cultured human epidermal melanocytes and HaCaT keratinocytes under UVA exposure; no living subjects
Recorded, and not evidence for this condition
Nonapeptide-1 acetate was applied to cultured human melanocytes as a comparator agent and reduced melanin content and tyrosinase activity in the dish. No study on file measured pigmentation in a living person: nothing here is skin lightening in a human, and the step from a cell assay to a visible change in melasma or post-inflammatory hyperpigmentation is an argument, not a result. The one human trial that includes nonapeptide-1 is a proprietary multi-ingredient melasma maintenance formulation with phenylethyl resorcinol, aminoethyl phosphinic acid, antioxidants and sunscreen, which attributes nothing to the peptide.
Source DOI 3 primary sources read for this row
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Melasma
in vitro Mechanistic only Not approved for this condition
- Who was studied
- cultured human epidermal melanocytes and HaCaT keratinocytes under UVA exposure; no living subjects
Recorded, and not evidence for this condition
Nonapeptide-1 acetate reduced melanin content and tyrosinase activity in cultured human melanocytes. No study measured melasma in a living person: the only human trial that includes nonapeptide-1 is a proprietary multi-ingredient melasma maintenance formulation with phenylethyl resorcinol, aminoethyl phosphinic acid, antioxidants and sunscreen, which attributes nothing to the peptide. The link from a cell assay to a visible change in melasma is an argument, not a result.
Source DOI 3 primary sources read for this row
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1 graded row, 1 source
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Skin ageing
in vitro Mechanistic only Not approved for this condition
- Who was studied
- cultured human dermal fibroblasts and UV-damaged human skin biopsy tissue ex vivo; no living human or animal subjects
Recorded, and not evidence for this condition
This is the same molecule the source names by its INCI name, copper tripeptide-1, and the same single study: elastin expression, elastase inhibition and elastic-fibre architecture in fibroblast culture and ex vivo UV-damaged human skin. No study measured a skin-ageing outcome in humans — no wrinkle, elasticity or photographic measure was taken in any living person, and no trial of topical or injected GHK-Cu for skin ageing is on file. The connection to skin ageing rests entirely on fibroblast and ex vivo elastin expression and is a mechanistic argument, not a result; a 2025 review of topically applied GHK states plainly that clinical studies are absent.
Source DOI 2 primary sources read for this row
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Checked, and nothing on file
24 compounds were read against these conditions and produced no gradeable row. They are named here rather than left off, because a list of 9 reads identically whether 9 survived 33 or 9 were all anyone thought of.
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Acetyl Tetrapeptide-11
No rung — nothing on file to grade
Checked against skin ageing, skin laxity. No study meeting the rubric was found for any of them.
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Acetyl Tetrapeptide-5
No rung — nothing on file to grade
Checked against skin ageing, skin laxity. No study meeting the rubric was found for any of them.
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Acetyl Tetrapeptide-9
No rung — nothing on file to grade
Checked against skin ageing, skin laxity. No study meeting the rubric was found for any of them.
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C-Max
No rung — nothing on file to grade
Checked against skin ageing. No study meeting the rubric was found for any of them.
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C-Type Natriuretic Peptide (CNP)
No rung — nothing on file to grade
Checked against skin ageing. No study meeting the rubric was found for any of them.
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Dipeptide Diaminobutyroyl Benzylamide Diacetate
No rung — nothing on file to grade
Checked against skin ageing, facial wrinkles. No study meeting the rubric was found for any of them.
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Elastin Peptides
No rung — nothing on file to grade
Checked against skin ageing. No study meeting the rubric was found for any of them.
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Endothelin-1 on hyperpigmentation
No rung — nothing on file to grade Not approved for this condition
ET-1 is a keratinocyte-derived melanocyte mitogen and part of the ultraviolet tanning response, which is mechanism in cell culture. No study administers it to human skin with a pigmentation outcome, and the therapeutic interest in this pathway is again in blocking it.
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Hexapeptide-11
No rung — nothing on file to grade
Checked against skin ageing. No study meeting the rubric was found for any of them.
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Hyaluronic Acid Binding Peptide on skin dryness
No rung — nothing on file to grade Not approved for this condition
The one study pointing this way (PMID 36448643) designed a hyaluronic-acid-binding peptide to carry hyaluronic acid through mouse skin and confirmed it reached the dermis. It measured penetration and tolerability, not hydration, and no skin condition was assessed.
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Melanotan I on skin ageing
No rung — nothing on file to grade Not approved for this condition
No study has measured any skin-ageing endpoint for this compound.
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Melanotan I on photoageing
No rung — nothing on file to grade Not approved for this condition
Afamelanotide is approved for photoprotection in erythropoietic protoporphyria and has randomised trials in vitiligo and photodermatoses, but no trial has enrolled photoaged skin or measured a photoageing endpoint such as wrinkling, elastosis or dyschromia from cumulative sun exposure. The approved indication is prevention of phototoxic pain, not repair of photodamage.
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Melanotan I on facial wrinkles
No rung — nothing on file to grade Not approved for this condition
No study has measured wrinkles for this compound.
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Melanotan I on skin laxity
No rung — nothing on file to grade Not approved for this condition
No study has measured skin elasticity or laxity for this compound.
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Melanotan I on hyperpigmentation
No rung — nothing on file to grade Not approved for this condition
The direction is wrong. Melanotan-I (afamelanotide) is an MC1R agonist that increases eumelanin; the human record is of induced tanning, not of reducing pigment. No trial has used it to treat hyperpigmentation.
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Melanotan I on melasma
No rung — nothing on file to grade Not approved for this condition
No trial has used afamelanotide against melasma, and as a pigment-inducing agonist it is not a candidate for one.
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Melanotan I on skin dryness
No rung — nothing on file to grade Not approved for this condition
No study has measured hydration or trans-epidermal water loss for this compound.
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Myristoyl Pentapeptide-17 on skin ageing
No rung — nothing on file to grade Not approved for this condition
No human or animal study has tested this peptide against any skin-ageing endpoint. The efficacy claims trace to supplier material with no paper behind them.
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Myristoyl Pentapeptide-17 on photoageing
No rung — nothing on file to grade Not approved for this condition
No study has enrolled photoaged skin or measured a photoageing endpoint for this compound.
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Myristoyl Pentapeptide-17 on facial wrinkles
No rung — nothing on file to grade Not approved for this condition
No study of myristoyl pentapeptide-17 has measured a wrinkle. The peptide appears in the literature only inside eyelash and hair-growth serums (PMID 32308787, PMID 31049335), both open-label, multi-ingredient and manufacturer-funded, and eyelash growth is not a condition in this corpus.
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Myristoyl Pentapeptide-17 on skin laxity
No rung — nothing on file to grade Not approved for this condition
No study has used this compound against skin laxity in humans or animals.
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Myristoyl Pentapeptide-17 on skin dryness
No rung — nothing on file to grade Not approved for this condition
No study has measured hydration or trans-epidermal water loss for this compound.
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Oligopeptide-34
No rung — nothing on file to grade
Checked against hyperpigmentation. No study meeting the rubric was found for any of them.
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Palmitoyl Hexapeptide-12
No rung — nothing on file to grade
Checked against skin ageing. No study meeting the rubric was found for any of them.
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Palmitoyl Tetrapeptide-7
No rung — nothing on file to grade
Checked against skin ageing, photoageing. No study meeting the rubric was found for any of them.
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Palmitoyl Tripeptide-1
No rung — nothing on file to grade
Checked against skin ageing, facial wrinkles. No study meeting the rubric was found for any of them.
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Pentapeptide-18
No rung — nothing on file to grade
Checked against skin ageing, facial wrinkles, hyperpigmentation. No study meeting the rubric was found for any of them.
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Silk Peptides
No rung — nothing on file to grade
Checked against skin ageing, skin dryness. No study meeting the rubric was found for any of them.
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Simonson Alpha 1
No rung — nothing on file to grade
Checked against skin ageing. No study meeting the rubric was found for any of them.
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Soy Peptides
No rung — nothing on file to grade
Checked against skin ageing. No study meeting the rubric was found for any of them.
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Tetrapeptide-21
No rung — nothing on file to grade
Checked against skin ageing, facial wrinkles. No study meeting the rubric was found for any of them.
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Tripeptide-10 Citrulline
No rung — nothing on file to grade
Checked against skin ageing, facial wrinkles. No study meeting the rubric was found for any of them.
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Tripeptide-29
No rung — nothing on file to grade
Checked against skin dryness. No study meeting the rubric was found for any of them.
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Wheat Peptides
No rung — nothing on file to grade
Checked against skin dryness. No study meeting the rubric was found for any of them.
What this page does not say
It reports what was measured, in whom, and how directly. It does not say what to take or at what dose, and a position here is a record of study depth rather than a reason to use anything. A compound at the top of this list is the most studied against these conditions; that is not the same claim as the most effective, and nothing on this page makes the second one.
Browse by goal
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