Marine Algae
Marine algae is rated 3 on our list, in the moderate 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 marine algae comedogenic?
Marine Algae is rated 3 on the comedogenic scale, which is the moderate band.
A catch-all term for seaweed extracts used to hydrate, plump, and mineralize the skin.
- Comedogenic rating
- 3 out of 5
- Band
- Moderate: Borderline plugging in the rabbit-ear test. Worth a look in a leave-on product.
- 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
- Seaweed / Marine Algae
- Also written as
- No common variants recorded
What a 3 means in practice
Three is the middle of the scale. Fulton 1989 counted 2 to 3 as borderline in the rabbit-ear test: some plugging of the follicles, short of a clear positive. Whether it matters depends on how high it sits on the label and whether the product stays on your skin.
Two things change what this number is worth. Ingredients are listed in descending order of concentration, so marine algae near the top of a label matters far more than marine algae 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 3 on our list to a paper we have read. Neither paper we could read tests any algae, seaweed or seaweed extract. 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.
Others in the same family
Common questions
- Is marine algae comedogenic?
- Marine Algae is rated 3 on the comedogenic scale, which is the moderate band. We have not found a published study that grades it, so treat this number as unconfirmed.
- Is marine algae non comedogenic?
- No. Marine Algae is rated 3 on the comedogenic scale, which is the moderate band. That is the number on our list rather than a verdict on any product. We have not traced it to a published study, so treat it as unconfirmed.
- What is marine algae's comedogenic rating?
- 3 out of 5 on our list. It is classed as Seaweed / Marine Algae. 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.”