Shea Butter

Shea butter does not appear anywhere in the assay corpus we searched — not in Fulton, not in any of the eleven studies acne.org catalogues, not in the 2024 CIR dossier. It rates Clear on the absence of any evidence against it, which is a different and weaker thing than a test it passed.

What it is

A fat pressed from the kernel of the West African shea tree, Vitellaria paradoxa, which appears on labels under its older botanical name as Butyrospermum Parkii Butter. The kernel is 30–54% fat. That fat is dominated by two long-chain C18 fatty acids — stearic acid at roughly 26–50% and oleic acid at roughly 37–62%, with only 2.6–9% palmitic acid and very little of anything shorter. Alongside the fats sits an unusually large unsaponifiable fraction, 2–12% of the lipid, made up largely of triterpene alcohols and their cinnamate esters — alpha- and beta-amyrin, lupeol, butyrospermol. Those ranges are wide because shea butter is not one material — the numbers move with origin, harvest and refining. Formulators use it as an occlusive emollient and a structuring fat. It is what makes a body butter feel like a body butter.

Why we rate it Clear

We rate it Clear at LOW confidence — and until an external fact-check caught us, we were printing Moderate. That was an overclaim, and the mechanism behind it is worth explaining, because it was structural rather than careless. Our confidence is derived automatically from an evidence tier, and we had no tier meaning "we have searched and found nothing." The closest one available said "formulators broadly agree," which prints Moderate. So an ingredient with no assay of any kind was carrying the same confidence as one with a body of professional opinion behind it. We have added the missing tier rather than quietly nudging a number, because the gap in the vocabulary was the bug. The honest way to say why is to start with what is missing. Shea butter does not appear in any comedogenicity assay we have been able to find, in either direction. It does not appear in the results of Fulton's 1989 rabbit-ear panel as any source reports them. It is absent from all eleven comedogenicity studies acne.org catalogues across 1972 to 2009. And the 2024 Cosmetic Ingredient Review safety assessment of thirteen shea-derived ingredients — the most complete technical dossier that exists on this material, the document that would say so if a test existed — contains no comedogenicity data and does not use the word "acne" once. That is why our legacy score field is blank rather than zero. The 0-out-of-5 you will find attached to shea butter across the internet is not a measurement. It is an absence that got typed into a number field, and once it sits in the same column as coconut oil's measured 4, an untested ingredient starts to look tested and cleared. It was never on the bench. So the Clear rests on two things, and we will name both, and then say plainly what they are worth. The first is a structure-activity inference from Fulton: mid-chain fatty acids such as lauric and myristic produced the most follicular hyperkeratosis in his work, and larger fatty acids generally produced less. Shea butter is overwhelmingly C18. The second is the absence of any evidence against it, from anywhere, in fifty years of people hunting for comedogenic ingredients. Now the part that matters. Neither of those is a result, and the first one is weaker than it sounds. Fulton did not test shea butter, did not test any butter like it, and did not validate a rule that predicts an untested triglyceride mixture from its fatty-acid profile. We are reasoning from a pattern in his data to an ingredient that is not in it. That is a hypothesis, not a finding, and the honest name for a Clear built on it is a default, not a verdict. If somebody ran the assay tomorrow it could come back the other way, and we would have no grounds to be surprised.

What the evidence doesn’t tell you

Absence of evidence is a weaker thing than evidence of absence. There is no rabbit-ear assay of shea butter, no human comedone count, no cyanoacrylate follicular biopsy — and "no signal" and "no one looked" produce the same silence. Clear is the least-wrong call available here, not a clean bill of health, and if the study were ever run it could come back the other way. The mechanistic case is also less tidy than it first looks. Oleic acid makes up 37–62% of shea butter, and oleic acid was among the more comedogenic materials in Kligman and Kwong's 1979 rabbit-ear work. That is a genuine published argument against rating shea butter Clear, it is aimed at the exact reasoning we are using, and the reader deserves it: the same fatty-acid profile we lean on to defend this ingredient contains, as its largest single component, a compound another assay implicated. The family comparison cuts the other way, and here it is worth being precise, because "butter" is a texture, not a chemistry. Cocoa butter — which we rate Caution — is roughly 35–37% stearic and 36–40% oleic. Compositionally that is not far from shea at all. The clearest difference is palmitic acid, about a quarter of cocoa butter and under a tenth of shea, and palmitic is a C16, sitting inside the band Fulton identified as most active. But the difference that actually decides the two ratings is not chemistry, it is evidence. Cocoa butter has a dedicated 2022 human study behind it — Baek and colleagues, reflectance confocal microscopy on the upper back, significantly more microcomedones than untreated skin at two weeks and larger comedone diameter at two and four weeks. Shea butter has nothing we can find, in either direction. One of these butters has human evidence against it; the other, as far as we can tell, has never been looked at. Sharing a word on a label tells you nothing about either. Human data on shea does exist and does not help here. Hon and colleagues (2015, Hong Kong Medical Journal) ran 34 paediatric atopic-dermatitis patients on a proprietary cream containing shea butter extract for four weeks and measured SCORAD, skin hydration, transepidermal water loss and itch. Nobody in that trial counted a comedone, the material was an extract inside a finished formula rather than shea butter, and the subjects were not acne patients. Finally, "shea butter" names a range, not a substance: refining strips much of the unsaponifiable fraction that is chemically the most distinctive thing about it, and no comedogenicity work we can find has compared the refined and unrefined forms — because we have found no comedogenicity work on shea at all to compare.

Where you’ll see it

Body butters, hand and foot creams, lip balms, cleansing balms, rich or "barrier" facial moisturisers, and a large share of hair conditioners and masks. It is frequently in the top five ingredients of anything marketed as nourishing or reparative, which is precisely why its rating matters to people reading labels. It appears as Butyrospermum Parkii (Shea) Butter, and its relatives as Butyrospermum Parkii Butter Unsaponifiables, Shea Butter Glycerides, Shea Oleine and Hydrogenated Shea Butter — thirteen shea-derived ingredients are in cosmetic use, and they are not interchangeable.

Sources

Each source says what it actually is. Several widely-cited “sources” for comedogenic ratings are republishing the same 1989 assay, and counting them as independent agreement is how a thin evidence base gets made to look thick.

1. acne.org — "What is comedogenicity, and what ingredients are comedogenic? The full story" A republisher of the legacy assays, but a useful one: it catalogues all eleven published comedogenicity studies from 1972 to 2009 with their methods and findings. Cited here for the absence — shea butter appears nowhere in it, in any study, at any grade. That is the single most load-bearing fact on this page.
2. Cosmetic Ingredient Review. "Safety Assessment of Butyrospermum parkii (Shea)-Derived Ingredients as Used in Cosmetics" — FINAL REPORT, released 5 October 2017 The industry safety dossier on thirteen shea-derived ingredients, and the best composition data available — the fatty-acid table (palmitic 2.6–9%, stearic 25.6–50.2%, oleic 37.1–62.1%, linoleic 0.6–10.8%), the 2–12% unsaponifiable fraction, the triterpene alcohols. Also cited for a negative, and it is the strongest negative we have: the Expert Panel reviewed the full toxicological record on this material, and a full-text search of the report returns zero occurrences of "comedogen", zero of "acne" and zero of "rabbit ear". If shea butter had ever been assayed, this is the document where it would appear. Correcting the citation itself, because we had it wrong twice over. We were linking `shea042017tent.pdf` — the AMENDED TENTATIVE REPORT FOR PUBLIC COMMENT, released 28 April 2017 and still open for comment on its own title page. The FINAL report was released 5 October 2017 and is what we link now. We were also naming it as a 2024 Int J Toxicol article we had never opened. We now cite the document we actually read.
3. Fulton JE. "Comedogenicity and irritancy of commonly used ingredients in skin care products." J Soc Cosmet Chem 40:321–333 (1989) The primary source for the 0–5 scale that nearly every comedogenic list online still uses, including ours. Method: ingredient diluted to roughly 10% in propylene glycol, applied to the inner ear of New Zealand albino rabbits, three rabbits per assay, follicles scored for keratosis. Cited here mainly for what it does not contain — no source we have found attributes a shea butter score to it — and for its structure-activity finding that C10–C16 fatty acids are the most comedogenic and C18-and-longer among the least, which is the mechanism our Clear rests on. The oils it does report include cocoa butter and coconut butter, both graded 4.
4. Kligman AM, Kwong T. "An improved rabbit ear model for assessing comedogenic substances." Br J Dermatol 100:699–702 (1979) Sixteen ingredients, rabbit ear, 0–3 scale. Cited as the counterweight to our own reasoning: per acne.org's review of the comedogenicity literature, oleic acid was among the comedogenic materials here — and oleic acid is up to 62% of shea butter. It is the strongest published reason to doubt the mechanistic case for rating shea butter Clear, and it is aimed squarely at the argument we are making.
5. Baek JH et al. "Early detection of microcomedones induced by cocoa butter using reflectance confocal microscopy." J Cosmet Dermatol 21:3016–3021 (2022) A rare thing in this literature: a dedicated human comedogenicity study, not a rabbit ear. Reflectance confocal microscopy on human upper back, finding significantly more microcomedones than untreated skin at two weeks and larger comedone diameter at two and four weeks for cocoa butter. Cited here purely for the family contrast — it is the evidence cocoa butter has and shea butter does not.
6. Padilla FC, Liendo R, Quintana A. "Characterization of cocoa butter extracted from hybrid cultivars of Theobroma cacao L." Arch Latinoam Nutr 50(2):200–205 (2000) Gas-chromatography fatty-acid profile of cocoa butter — palmitic 22.9–26.1%, stearic 34.7–37.3%, oleic 36.2–39.9%. Cited for the family comparison, and for the inconvenient half of it: shea and cocoa butter are compositionally closer than their ratings imply, which is why the honest account of the gap between them is evidentiary rather than chemical.
7. Draelos ZD, DiNardo JC. "A re-evaluation of the comedogenicity concept." J Am Acad Dermatol 54:507–512 (2006) Peer-reviewed rebuttal of the rabbit-ear assay. Argues that its results do not reliably predict comedogenicity in human skin, and that testing an isolated ingredient says little about a finished formula. It cuts in the ingredient's favour here rather than against it, which is exactly why it needs saying: the same argument that weakens a 4 also weakens a 0 — and it weakens the C18 inference we are leaning on, too.
8. "Comedogenicity in cosmeceuticals: A review of clinical relevance, regulatory gaps, and future directions." JAAD Reviews (2025) Recent peer-reviewed review of the field, covering 1972 to 2025. Finds that no standardised comedogenicity test exists and that "non-comedogenic" is an unregulated label. It is a synthesis of the legacy literature, not a new measurement, and independent of Fulton only in authorship, since the corpus it surveys includes his. Context for why a fifty-year literature can simply never have got round to one of the most widely used fats in cosmetics.
9. Hon KL et al. "Patient acceptability, efficacy, and skin biophysiology of a cream and cleanser containing lipid complex with shea butter extract versus a ceramide product for eczema." Hong Kong Med J 21(5):417–425 (2015) The nearest thing to human data on shea, and it is not close. 34 paediatric atopic-dermatitis patients, four weeks, measuring SCORAD, hydration, transepidermal water loss and itch. Listed to show what it is not: it tested a proprietary cream containing shea butter extract, not shea butter, on eczema, not acne, and it counted no comedones.
10. Face Reality pore-clogging ingredient list An acne-clinic list, and one of the sources behind our own entry. It names Shea Butter as pore-clogging, in direct contradiction of our Clear verdict. It gives no citation, no method and no score. Unlike most such lists it cannot even be republishing Fulton on this point, because there is no Fulton score for shea butter to republish. We cannot refute it with evidence — we can only observe that it does not offer any, and that neither does anyone else.
11. CosDNA ingredient database The other aggregator behind our entry, and the likeliest origin of the 0 that circulates for shea butter. It publishes a 0–5 "acne" score per ingredient with no disclosed method, provenance or citation. Not an independent measurement, and on this ingredient not demonstrably a measurement at all — which is why we no longer carry its 0 as our legacy score.

Others in the same family

Butters behave similarly enough that the evidence for one is often wrongly read across to the others. These are its structural relatives, not a guess. What the evidence says about butters as a family ›

• Cocoa Butter Caution Moderate
• Coconut Butter Clogging Low

Last reviewed 2026-07-12 · How we decide

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