Ingredient ratings / Prunus Amygdalus Dulcis (Sweet Almond) Oil

Is almond oil comedogenic? What the rabbit-ear tests found

By Skinredients · Checked against the sources 2026-10-16

Label name

Prunus Amygdalus Dulcis (Sweet Almond) Oil

Also listed as

sweet almond oil, almond oil, prunus amygdalus dulcis oil

Comedogenic grade

1–3 / 5 · Borderline (2–3) or reported positive

Tests

• Fulton 1989: comedogenic 2/5, irritancy 0/5 — rabbit ear, 10% in propylene glycol (standard grade)
• Fulton 1989: comedogenic 1/5 — rabbit ear, 10% in propylene glycol (refined grade)
• Morris & Kwan 1983: comedogenic 3/5 — rabbit ear, undiluted

What the tests found

For sweet almond oil, the undiluted test came out higher than the diluted one.

Morris & Kwan 1983. This lab applied “Sweet Almond Oil” (supplier: Lipo Chemicals, Inc.) undiluted to the ear canals of three rabbits, 14 times over about three weeks. Follicles were graded under the microscope against the untreated ear. The oil scored 3 out of 5, which their scale describes as a marked increase of keratin in the follicle, distending it, with moderate hyperplasia of the follicle lining [2]. Most vegetable oils in their study were negative or only slightly reactive. They single out grape seed and sweet almond oil as more reactive, producing enlarged follicles packed with loose horny material [2].

Fulton 1989. Fulton tested an oil printed simply as “Almond oil”, diluted to 10% in propylene glycol, on three rabbits for two weeks. It graded 2 for follicle plugging and 0 for irritation. A refined almond oil graded 1 [1]. That places the standard oil in his borderline band and the refined one just below it, and like every oil in his table it is flagged as varying with the raw-material source [1]. Apricot kernel oil scored the same pair of grades in that table, 2 and 1 refined [1].

Where the evidence is weaker (or disagrees)

• Different samples, possibly different oils. Fulton’s label doesn’t say whether his “almond oil” was sweet almond oil. Morris and Kwan specify sweet almond [1][2]. Both used one commercial lot each.
• The fatty-acid argument. Morris and Kwan’s Table III lists their sweet almond oil as 70% oleic and 20% linoleic acid. They saw no consistent link between chain length and grade across vegetable oils. They did note a trend toward greater potency in oils with comparatively high combined oleic and linoleic content, while high-oleic olive and avocado oils showed no activity [2]. The Cosmetic Ingredient Review (CIR) gives sweet almond oil’s composition as 62–86% oleic and 20–30% linoleic acid [4]. That linoleic share is higher than its range for avocado (10–12%), though olive’s range (3.5–20%) overlaps at the top [4]. This pattern is the authors’ observation across nine oils, not a tested mechanism.
• Dilution reduces activity. Morris and Kwan report that Kligman and Mills found vegetable oils inactivated when diluted to 25% in mineral oil [2]. That fits Fulton’s lower grade at 10%, but the two labs also differed in method and sample. It isn’t a clean dose comparison.
• Rabbit, not human. The rabbit ear is the more sensitive model (see the comedogenic scale). Still, in Mills and Kligman’s human back test, substances that were moderately to strongly comedogenic in rabbits could also induce comedones in people [3]. A 3 is in the moderate band on Morris and Kwan’s scale [2], but sweet almond oil itself has no human comedogenicity test in these sources.

Where it shows up, and how much

Sweet almond oil is one of the most widely used plant oils in cosmetics. In the CIR’s 2017 assessment of plant-derived fatty acid oils, it had 1,127 uses. The report names only shea butter (1,950) and sunflower seed oil (1,414) as more widely used [4]. The report compares older and newer data:

• Products: 375 in 2002, rising to 1,127 in 2010
• Concentrations: 0.004–76% in 2002, then 0.0001–77% in 2010
• Leave-on products: 791 uses, up to 77%
• Products in skin contact: 986 uses, up to 46%
• Nail products: 13 uses, up to 77%. This is where the highest concentration is.
• Bath products: 41 uses, up to 43%
• Products on mucous membranes: 93 uses, up to 23%
• Baby products: 14 uses, 2–3%

In the CIR’s table, the highest skin-contact concentration (46%) is lower than the oil Morris and Kwan tested (100%). Their 3/5 grade was for a much stronger exposure than most products deliver.

If you want to avoid it

The grade that sets sweet almond oil apart is Morris and Kwan’s undiluted 3, so the useful comparison is with oils that lab also tested neat and graded lower:

• Castor oil: 0–1 undiluted (Morris & Kwan 1983), and 1 at 10% (Fulton 1989) [1][2]
• Safflower oil: 1–2 undiluted (Morris & Kwan 1983), and 0 at 10% (Fulton 1989) [1][2]
• Sesame oil: 1 undiluted (Morris & Kwan 1983). Fulton graded a standard sample 3 and a refined one 1, so the source matters [1][2].

Apricot kernel oil (2, or 1 refined) and peach kernel oil (2 in Morris & Kwan) are graded about the same as almond oil, so they are not lower-graded swaps [1][2]. The INCI label name to look for is Prunus Amygdalus Dulcis (Sweet Almond) Oil.

Sources

1. Fulton JE Jr. Comedogenicity and irritancy of commonly used ingredients in skin care products. J Soc Cosmet Chem. 1989;40(6):321-333. https://library.scconline.org/v040n06/13
2. Morris WE, Kwan SC. Use of the rabbit ear model in evaluating the comedogenic potential of cosmetic ingredients. J Soc Cosmet Chem. 1983;34(5):215-225. https://library.scconline.org/v034n05/1
3. Mills OH Jr, Kligman AM. A human model for assessing comedogenic substances. Arch Dermatol. 1982;118(11):903-905. https://pubmed.ncbi.nlm.nih.gov/7138047/
4. Burnett CL, Fiume MM, Bergfeld WF, et al. Safety Assessment of Plant-Derived Fatty Acid Oils. Int J Toxicol. 2017;36(Suppl 3):51S-129S. https://cir-reports.cir-safety.org/view-attachment/?id=ad62ac6b-8e74-ec11-8943-0022482f06a6 (abstract: https://pubmed.ncbi.nlm.nih.gov/29243540/)

Comedogenic grades describe single raw materials tested in a lab, usually on rabbit ears. They are a guide for acne-prone skin, not a prediction for any product or person, and this page is not medical advice. How the scale works.