Isostearyl Alcohol
Isostearyl alcohol is rated 2 on our list, in the low band, and that number is unconfirmed: we have not traced it to a published study (what unconfirmed means).
Like every rating here, it is for the raw ingredient tested alone, and a label does not print how much of it a product holds.
Is isostearyl alcohol comedogenic?
Isostearyl Alcohol is rated 2 on the comedogenic scale, which is the low band.
A fatty alcohol used to soothe the skin and stabilize emulsions.
- Comedogenic rating
- 2 out of 5
- Band
- Low: Little plugging in the rabbit-ear test. Fulton 1989 counts 0 to 1 as not significant and 2 as borderline.
- Where the number comes from
- Unconfirmed. We could not trace this rating to a study we have read; the section on who rated it says what we checked.
- Composition
- Fatty Alcohol
- Also written as
- No common variants recorded
What a 2 means in practice
One and two are the low band. In the rabbit-ear test, Fulton 1989 counted 0 to 1 as not significant and 2 as borderline. A low grade on a rabbit's ear, which reacts more readily than human skin, is weak evidence of a problem on a person.
Two things change what this number is worth. Ingredients are listed in descending order of concentration, so isostearyl alcohol near the top of a label matters far more than isostearyl alcohol at the bottom. And the rating describes the raw ingredient on its own. A 2006 review in the Journal of the American Academy of Dermatology found that a rating for a single ingredient does not reliably predict how a finished formula behaves on human skin. The full story of the scale is here.
Who rated it
We could not trace the 2 on our list to a paper we have read. Neither paper we could read tests isostearyl alcohol. The list does not say where its numbers came from, so treat this number as unconfirmed rather than as one we can tie to a table.
Common questions
- Is isostearyl alcohol comedogenic?
- Isostearyl Alcohol is rated 2 on the comedogenic scale, which is the low band. We have not found a published study that grades it, so treat this number as unconfirmed.
- Is isostearyl alcohol non comedogenic?
- Not exactly. Isostearyl Alcohol is rated 2, which is the low band rather than 0. Low and non-comedogenic are different things, and only a 0 means the second one.
- What is isostearyl alcohol's comedogenic rating?
- 2 out of 5 on our list. It is classed as Fatty Alcohol. We have not found a published study that grades it, so treat this number as unconfirmed.
Sources we checked this rating against
- Kligman AM, Kwong T. “An improved rabbit ear model for assessing comedogenic substances.” British Journal of Dermatology, June 1979;100(6):699–702. (opens in a new tab) The rabbit-ear assay behind published 0 to 5 comedogenicity grades.
- Fulton JE Jr. “Comedogenicity and irritancy of commonly used ingredients in skin care products.” Journal of the Society of Cosmetic Chemists, November/December 1989;40(6):321–333. (opens in a new tab) Rabbit ear. Each ingredient at 10 percent in propylene glycol unless stated, applied five days a week for two weeks, and graded 0 to 5 from the width of the follicles, measured by micrometer and under the microscope. The paper counts 0 to 1 as not significant, 2 to 3 as borderline and 4 to 5 as positive. Some grades depended on the supplier of the raw material, and some oils were also tested refined.
- Draelos ZD, DiNardo JC. “A re-evaluation of the comedogenicity concept.” Journal of the American Academy of Dermatology, March 2006;54(3):507–512. doi:10.1016/j.jaad.2005.11.1058 (opens in a new tab) Tested finished products on the backs of six people and concluded that “Finished products using comedogenic ingredients are not necessarily comedogenic.”