Red Algae
Red Algae is rated 5 on the comedogenic scale, which is the high risk band.
A broad class of seaweeds used for gelling and intense hydration; highly comedogenic.
- Comedogenic rating
- 5 out of 5
- Band
- High risk: A high chance of blocking pores in anyone acne-prone.
- Composition
- Marine Extract / Seaweed / Marine Algae
- Also written as
- No common variants recorded
What a 5 means in practice
A 4 or 5 is the top of the scale. In the research the scale came from, ingredients in this band blocked follicles in most people prone to acne, so it is the band to keep out of anything that stays on your skin. In a rinse-off product, contact time is short and the risk is lower.
Two things change what this number is worth. Ingredients are listed in descending order of concentration, so red algae near the top of a label matters far more than red 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.
Others in the same family
- Ascophyllum Nodosum 4 High risk
- Caulerpa Lentillifera Extract 4 High risk
- Chaetomorpha Linum 4 High risk
- Cladosiphon Okamuranus Extract 4 High risk
- Dictyopteris Membranacea 4 High risk
- Dunaliella Salina Extract 4 High risk
- Gelidiella Acerosa Extract 4 High risk
- Gigartina Stellata Extract 4 High risk
Where red algae comes up on this site
Common questions
- Is red algae comedogenic?
- Red Algae is rated 5 on the comedogenic scale, which is the high risk band.
- Is red algae non comedogenic?
- No. Red Algae is rated 5 on the comedogenic scale, which is the high risk band. That is a published rating for the ingredient rather than a verdict on any product containing it.
- What is red algae's comedogenic rating?
- 5 out of 5. It is classed as Marine Extract / Seaweed / Marine Algae.
Sources for this rating
- 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 that produced most of the 0–5 numbers still quoted today.
- Fulton JE Jr, Pay SR, Fulton JE 3rd. “Comedogenicity of current therapeutic products, cosmetics, and ingredients in the rabbit ear.” Journal of the American Academy of Dermatology, January 1984;10(1):96–105. (opens in a new tab) The published ingredient-by-ingredient ratings that most comedogenic lists, including this one, trace back to.
- 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) Found that animal-model results did not reliably predict what happened on human skin, and that a rating for a single ingredient does not tell you how a finished product will behave.