What is Isocetyl Stearate?
Chemically, Isocetyl Stearate is a synthetic emollient ester. A heavy emollient ester that leaves a rich, cushioned feel. Non-irritating but a maximum 5/5 on the comedogenic scale.
Where Isocetyl Stearate shows up
Isocetyl Stearate is commonly formulated into lotions, sunscreens, primers, and colour cosmetics, where it adds a smooth, non-greasy slip. Separately from clogging, its irritancy is rated 0/5 — low, so it's unlikely to sting or sensitise on its own.
Is Isocetyl Stearate bad for acne-prone skin?
If you are acne-prone, Isocetyl Stearate is one to watch — especially when it appears in the first few ingredients, which means it's present at higher concentration. Lower down a long ingredient list, its practical impact drops considerably.
Note for fungal-acne (malassezia) sufferers: Isocetyl Stearate is commonly avoided in fungal-acne routines, since it falls into the fatty-acid or ester families the yeast can feed on. The evidence there is looser than for comedogenicity — see our fungal-acne checker for context.
Non-comedogenic alternatives
If you're avoiding Isocetyl Stearate, these lower-risk ingredients serve a similar role and are gentler on pore-prone skin:
- Caprylic/Capric Triglyceride — rated 1/5 (Low risk).
- Squalane — rated 1/5 (Low risk).