Ingredient Beauty BenefitsPeptide · Palmitoyl Pentapeptide-4
Palmitoyl pentapeptide-4: the concentration that worked was 3 ppm — 0.0003%
In a 12-week, double-blind, split-face trial in 93 people, a moisturiser containing 3 ppm significantly outperformed the same moisturiser without it for fine lines and wrinkles. Three ppm is 0.0003%. It is a number that makes 'high concentration' on a label worth rereading.
Last checked Sep 17, 2026
Start here
- What it is
A peptide of five amino acids with a fatty acid attached. Known by the trade name 'Matrixyl'.
- What it is used for
Products aimed at wrinkles.
- How it is said to work
It is said to mimic a fragment released when collagen breaks down, so the skin reads it as 'collagen is short' and makes more. Note that the concentrations used are measured in ppm.
There are no numbers and no citations in this box. What has been established, and how far, is below.
At a glance
- In pregnancy
- Not established
- Irritation
- Minimal
- Daytime use
- ✓ Fine
- How well established
- Moderate evidence
- Concentration studied
- 3 ppm
- Length of the studies
- 8–12 weeks
Not a measurement — reported irritation grouped into five steps. It varies between people.
“Concentration studied” and “Length of the studies” are taken straight from the research on this page. They are not a recommended dose, and the figure for each finding is written out in the text.
This is not how large the effect is but how well confirmed it is. It shows the highest grade among the findings on this page.
Palmitoyl pentapeptide-4 is five amino acids — lysine-threonine-threonine-lysine-serine, or KTTKS — with palmitic acid attached. It is better known by the trade name Matrixyl.
There is a reason for the palmitic acid. The peptide itself is water-loving and does not cross an oily stratum corneum well; the fatty tail is an attempt to fix that.
This is not a notified wrinkle active in Korea. Annex 4 lists only four for wrinkles — retinol, retinyl palmitate, adenosine and polyethoxylated retinamide. No peptide is on it.
Contents
What is established
The same ingredient at a different strength, in a different formula, is a different product. These are the conditions the studies used.
Three ppm beat the vehicle in 93 people
A 12-week, double-blind, placebo-controlled, split-face randomised study published in 2005. Ninety-three Caucasian women aged 35 to 55 took part.
The comparison is well built. One side received a moisturiser; the other received the same moisturiser with 3 ppm of pal-KTTKS added and nothing else changed. Same person, same face, one difference.
The result was significant: wrinkles and fine lines improved against the placebo control on both quantitative technical analysis and expert grader image analysis. Self-assessment also showed significant fine line improvement.
What stays with you from this trial is the concentration. Three parts per million is 0.0003%. That is one two-hundred-and-fiftieth of retinol's notified 0.075%.
How should that be read? It says two things at once. One is that this molecule works at a very small dose. The other is that 'high peptide content' on a label does not connect to the evidence. What was demonstrated is 3 ppm, not something higher. We found no trial showing that more is better.
One more note: this paper appeared in a cosmetic science journal (Int J Cosmet Sci). The abstract does not state a funding source, so we mark funding as unclear.
- Randomised controlled trial in people · 93 participants · 12 weeks · Compared with vehicle (same formula minus the active) · Funding not declared · Endpoint scores from blinded assessors PMID 18492182 · abstract read
The 2023 crow's feet trial had seven people per arm
A double-blind randomised trial run in Indonesia in 2023. Twenty-one women aged 26 to 55 were split into three groups: acetyl hexapeptide-3 cream, palmitoyl pentapeptide-4 cream and placebo, applied twice daily to the periorbital area for eight weeks.
Assessment used Corneometer, Tewameter, Cutometer, digital photography and a Crow's Feet Grading Scale.
The palmitoyl pentapeptide-4 arm did better than both the acetyl hexapeptide-3 arm and placebo. But the authors themselves wrote in the conclusion that this is an initial study, providing an opportunity for further work with a more adequate sample size and duration.
Twenty-one people across three groups is seven per arm. A difference arising in seven people can easily be chance. That is why the authors' wording is careful, and it is why we grade this item as early evidence.
The authors also lean on photographs and a self-assessment questionnaire in reaching their conclusion — the result does not rest on the grading scale alone.
- Randomised controlled trial in people · 21 participants · 8 weeks · Compared with vehicle (same formula minus the active) · Funding not declared · Endpoint scores from blinded assessors PMID 36909866 · abstract read
Whether peptides cross the stratum corneum is an old question
There is a widely cited rule of thumb in skin absorption: molecules above 500 daltons struggle to cross intact stratum corneum. A five-amino-acid peptide sits near or above that line.
Attaching the palmitic tail is aimed precisely at this problem — raising lipid affinity so the molecule can get through.
But we found no data directly confirming, in human skin, that the design does what it is meant to. The trials above looked at what happened to wrinkles after application, not at how far the molecule travelled.
An observed effect and a confirmed mechanism are different things. We keep this as a separate item so that a clinical result is not quietly used as proof that the mechanistic story is right.
How to use it
- Most products do not disclose the amount. The concentration with evidence behind it is 3 ppm, but an ingredient list gives you order, not numbers.
- The trial above ran 12 weeks; the eight-week one was preliminary. Judging sooner is hard.
- It is very rarely irritating, so it gets suggested as an alternative for skin that cannot tolerate retinol. We found no trial comparing it directly with retinol. 'Alternative' there is an expectation, not evidence.
Cautions
- Irritation reports are rare. The 2005 trial recorded good skin tolerance.
- We found no established data on use during pregnancy.
- Carrying a wrinkle functional claim with this ingredient requires review in Korea. The word 'peptide' on the front of a bottle may have nothing to do with that review.
With a new ingredient, apply a small amount somewhere inconspicuous, such as the inner arm, for two days first. Stop if it reddens or stings.
Related skin concerns
What this article relies on
Unless marked otherwise, a paper was read to the abstract. Only papers whose full text we opened are marked as such.
- PubMed — 미국 국립의학도서관 문헌 데이터베이스National Library of Medicine · Checked on 2026-09-16