Ingredient · dataset v56
Polyhydroxystearic Acid and fungal acne
May trigger · Limited evidence
Why it's a potential trigger
A polymer of hydroxystearic (C18-OH) acid; same hydroxylated-C18 caution as the ruled Ethylhexyl Hydroxystearate.
Explicit row.
Evidence strength
Limited evidence (1/3)
Function
Fatty ester
Fatty esters: split by the yeast’s enzymes into edible fats.
Products without this ingredient
- CLn 2-in-1 Gentle Wash & Shampoo 8 fl oz
- SVR Sebiaclear Foaming Gel 400 ml
- LANE & CO. Baby Hair Gel 4 fl oz
- Lily Lolo Mineral Foundation SPF 15 In The Buff 10 g
- Sky Organics Indian Healing Clay 16 oz
- Avene Micellar Cleansing Water 3-in-1 200 ml
Related fatty ester
- Ascorbyl Palmitate — May trigger · Moderate evidence
- Ascorbyl Tetraisopalmitate — May trigger · Moderate evidence
- Behenyl Acrylate — May trigger · Limited evidence
- Behenyl Behenate — May trigger · Limited evidence
- Bis-Octyldodecyl Dimer Dilinoleate/Propanediol Copolymer — May trigger · Moderate evidence
- Butylene Glycol Dicaprylate/Dicaprate — No known trigger
- Butyloctyl Salicylate — May trigger · Limited evidence
- C12-15 Alkyl Benzoate — May trigger · Limited evidence
Sources
- Brunke & Hube 2006 — MfLIP1 extracellular lipase hydrolyses Tweens (Microbiology)
- Mayser et al. 1995 — ester hydrolysis depends on alcohol moiety (Acta Derm Venereol)
- EU CosIng database — search the INCI name
Last reviewed: 2026-10-13 (dataset v56).
Questions
Does Polyhydroxystearic Acid trigger fungal acne?
We flag it as a potential trigger (limited evidence). That means it belongs to a class the Malassezia yeast is known to feed on — not that every product with it will cause a flare. Concentration, formulation and individual skin chemistry matter.
Does Polyhydroxystearic Acid feed Malassezia?
Yes: we flag Polyhydroxystearic Acid as a potential trigger (limited evidence). It belongs to a class Malassezia is known to feed on — not a claim that every product with it causes a flare. Concentration, formulation and individual skin chemistry matter.
How confident is this call?
Limited evidence: A polymer of hydroxystearic (C18-OH) acid; same hydroxylated-C18 caution as the ruled Ethylhexyl Hydroxystearate.
Is this medical advice?
No. We screen ingredient lists; we never diagnose, treat, or certify products. When in doubt, ask a dermatologist.
Check a full list containing Polyhydroxystearic Acid →
Not medical advice: we screen ingredient lists for potential triggers — we never diagnose, treat, or certify products. Dataset v56.