Acetyl dipeptide-1 cetyl ester is one of the few cosmetic peptides with a human test in the people it is sold to. That alone makes it worth a close read: it is listed in creams for sensitive, easily stung skin, and the one published trial of a product containing it was run in exactly that group. The result is less flattering than the marketing implies. This page covers the molecule, the five indexed papers on it as of 22 October 2026, and what the trial measured.
A brain dipeptide with a fatty tail
PubChem's record (CID 11685829) names it hexadecyl acetyl-L-tyrosyl-L-argininate: C33H57N5O5, 603.8 daltons. The record also lists Sensicalmine, the name under which it is sold to formulators. Taken apart:
- Tyrosine–arginine is the peptide. That pair has its own name and literature: kyotorphin (PubChem CID 123804), a dipeptide first found in the brain and studied for its part in pain signalling. PubMed held 255 kyotorphin records on 22 October 2026; only one joins it to skin, a 2005 laboratory study of pushing a modified kyotorphin through skin with an electric current (PMID 16169627).
- Acetyl caps the tyrosine end.
- Cetyl ester attaches cetyl alcohol, a 16-carbon fatty alcohol, to the arginine end. It plays the same role as the palmitoyl tag on other cosmetic peptides, making a charged, water-loving molecule more at home in the skin's oily outer layer.
The kyotorphin link explains the pitch — a pain-pathway dipeptide aimed at skin that stings. It does not establish the effect: the brain studies concern the unmodified peptide in nerve tissue, and the cosmetic molecule is a different chemical with a different route.
The five papers
PubMed returned the same five records for the quoted INCI name, the unquoted form, and a search for “acetyl dipeptide-1” combined with the trade term Idealift; none is tagged as retracted.
| Paper | Who wrote it | What it did with the peptide |
|---|---|---|
| Schoelermann et al. 2016, JEADV supplement | Beiersdorf R&D | Human test: two finished products compared split-face in 31 women with sensitive skin (below) |
| Sulzberger et al. 2016, same supplement | Beiersdorf R&D | Cell tests: no effect on TRPV1 activation; lowered inflammatory signals only at higher concentrations than licochalcone A |
| Khmaladze et al. 2019, J Cosmet Dermatol | Oriflame Skin Research Institute | Cell and skin-explant work for a multi-active formula: switched on barrier genes (aquaporin-3, filaggrin, caspase-14, keratin-10) and dermal genes in cultured cells |
| Resende et al. 2021, Pharmaceuticals | University of Porto | Review: one of seven peptides found in 88 sensitive-skin products |
| Ferreira et al. 2022, Int J Cosmet Sci | University of Porto | Review: among the top actives, one of only three studied on volunteers with sensitive skin |
Three of the five are company research, and two of those three come from Beiersdorf, which makes the competing product in the only human test.
The one human test
The 2016 study enrolled 31 women aged 19 to 65 who described their skin as sensitive or very sensitive. After three days without facial products, each had a 40 ppm capsaicin cream applied — capsaicin is the chilli compound that causes burning through the TRPV1 receptor — and only those who reacted continued. Then one product went on the right nasolabial fold and the other on the left, at random, and burning was rated over 15 minutes.
The two products were Eucerin UltraSensitive Soothing Care, with 4-t-butylcyclohexanol, and La Roche-Posay Toleriane Ultra Intense Soothing Care, with acetyl dipeptide-1 cetyl ester. The results, as the abstract reports them:
- Both products reduced the capsaicin burning during the 15 minutes.
- The 4-t-butylcyclohexanol product gave significantly lower burning at one and two minutes.
- There was no significant difference in the time of the worst burning, its severity or its duration.
Three limits sit on top of the result. It compares two whole formulas, not the peptide against its absence, so it cannot separate the peptide from everything else in the La Roche-Posay cream. There was no untreated or vehicle side, so the share of the relief that would have happened anyway as capsaicin wears off is unknown. And the authors worked for Beiersdorf, the maker of the Eucerin product that came out ahead — a test run by one brand on a competitor's product.
The lab picture does not line up neatly
Beiersdorf's companion cell paper explains its choice of competitor: acetyl dipeptide-1 cetyl ester did not block TRPV1, the burning receptor, while 4-t-butylcyclohexanol did. That fits the split-face result, where the TRPV1 blocker acted faster. Oriflame's cell work, by contrast, credits the peptide with barrier and collagen-related gene activity, which is a slower, different claim from stopping a sting. Neither group tested the peptide on its own in people, and neither has an outside replication in PubMed.
Where it fits among sensitive-skin ingredients
The Porto survey of 88 pharmacy-channel products is the best map of the category. Niacinamide led the ingredient count, followed by oat, allantoin and glycyrrhetinic acid; peptides were in 17% of the products. Among the leading actives, only niacinamide, panthenol and this peptide had any study in volunteers with sensitive skin. The authors' overall verdict was that clinical studies for these ingredients “remain sparse and lack methodological quality”. The other calming peptide named in that survey, palmitoyl tripeptide-8, has no human study at all.
For skin that reacts to almost everything, the conditions behind it — rosacea, eczema, contact allergy — have their own trial records, counted on our rosacea and eczema pages, and a dermatologist is the person to sort one from another.
What can fairly be said
Acetyl dipeptide-1 cetyl ester is a lipid-tagged form of a pain-pathway dipeptide, used in soothing creams. It has more human data than most cosmetic peptides — one randomized split-face test — and in that test a product with a different calming agent relieved stinging faster. Its laboratory record is company-written and mixed. A cream that lists it contains it; the published evidence does not show the peptide alone calming skin.
Sources
Opened 22 October 2026: PubChem CID 11685829 (structure, synonyms) and CID 123804 (kyotorphin); PubMed searches "acetyl dipeptide-1 cetyl ester", dipeptide-1 cetyl ester and idealift OR "acetyl dipeptide-1" (5 each), retraction filter (0), kyotorphin (255) and kyotorphin AND (skin OR cosmetic*) (1); abstracts of PMIDs 26805418, 26805417, 31584241, 34451799, 34813665 and 16169627. Corrections go to the contact page.