What a 1/5 rating means
On the comedogenic scale, a 1 sits at the safe end of the scale — clogging is unlikely for most people. That places Squalene in the range most people, including many with acne-prone skin, tolerate well.
This rating is disputed. Credible sources land on different numbers for Squalene, so we publish the range (1) 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 Squalene near the end of a label is present in tiny amounts and matters far less than the same ingredient near the top.
About Squalene
It is a lightweight emollient chosen for slip without heaviness. The unsaturated parent of squalane, rated around 1 but prone to oxidation, which raises real-world clogging risk. Distinct from the more stable squalane.
On a label it can read as Squalene, Shark Squalene, Shark Liver Oil — worth knowing when you scan an ingredient deck.
Squalene in makeup and skincare
It is a favourite in 'skin-friendly' foundations and lightweight moisturisers. Its irritancy is rated separately at 0/5, which is low.
If you deal with fungal acne (malassezia folliculitis) rather than ordinary clogged pores, note that Squalene is among the fatty-acid or ester-type ingredients that community sources commonly avoid — a separate concern from its comedogenic score, and one with weaker evidence behind it.