What a 4/5 rating means
On the comedogenic scale, a 4 is in the high-risk band, with a real likelihood of clogging pores on acne-prone skin. That means Ascophyllum Nodosum (Knotted Wrack) deserves attention if you break out easily, especially when it appears high on an ingredient list.
This rating is disputed. Credible sources land on different numbers for Ascophyllum Nodosum (Knotted Wrack), so we publish the range (4) rather than a false single figure. When sources disagree this openly, your own experience carries real weight.
One thing the number cannot tell you is concentration. Ingredients are listed in descending order, so Ascophyllum Nodosum (Knotted Wrack) near the end of a label is present in tiny amounts and matters far less than the same ingredient near the top.
About Ascophyllum Nodosum (Knotted Wrack)
It is a marine or algae extract, marketed for minerals and antioxidants. A brown seaweed extract grouped with the high-rated marine ingredients on pore-clogging lists.
On a label it can read as Ascophyllum Nodosum, Ascophyllum Nodosum Extract, Ascophyllum, Bladderwrack — worth knowing when you scan an ingredient deck.
Ascophyllum Nodosum (Knotted Wrack) in makeup and skincare
It features in 'anti-ageing' serums, masks, and luxury complexion products. Its irritancy is rated separately at 2/5, which is low.
Lower-rated alternatives to Ascophyllum Nodosum (Knotted Wrack)
If you want a similar role with a friendlier comedogenic score, consider:
- Hyaluronic Acid — comedogenic rating 0/5 (Low risk).
- Niacinamide — comedogenic rating 0/5 (Low risk).