Is Polyhydroxystearic Acid fungal acne safe?
Polyhydroxystearic Acid is best used with caution for fungal-acne-prone skin. Polyester of 12-hydroxystearic acid. The monomer, Hydroxystearic Acid, is avoid; polymerisation should reduce availability, but the ester bonds can in principle hydrolyse. Evidence is thin either way.
Why this verdict
Polyester of 12-hydroxystearic acid. The monomer, Hydroxystearic Acid, is avoid; polymerisation should reduce availability, but the ester bonds can in principle hydrolyse. Evidence is thin either way.
Fungal acne, properly called malassezia folliculitis, is driven by a yeast that feeds on fatty acids in roughly the C11 to C24 range. An ingredient is a concern when it can supply usable fatty acids in that window, and it is generally fine when it cannot. Chain length and ethoxylation can both change the verdict, which is why the chemical family alone does not decide it. See the full trigger list and how we assess ingredients for the reasoning and sources.
Safer swaps
Fungal-acne-safe alternatives in the same category (Polymer):
Frequently asked questions
Is Polyhydroxystearic Acid safe for fungal acne?
Polyhydroxystearic Acid is best used with caution for fungal-acne-prone skin. Polyester of 12-hydroxystearic acid. The monomer, Hydroxystearic Acid, is avoid; polymerisation should reduce availability, but the ester bonds can in principle hydrolyse. Evidence is thin either way. This is informational only and not a diagnosis; suitability varies by person and formulation.
Why does Polyhydroxystearic Acid trigger fungal acne?
Polyester of 12-hydroxystearic acid. The monomer, Hydroxystearic Acid, is avoid; polymerisation should reduce availability, but the ester bonds can in principle hydrolyse. Evidence is thin either way. Fungal acne (malassezia folliculitis) is driven by ingredients that supply fatty acids in roughly the C11 to C24 range that the yeast can metabolize; Polyhydroxystearic Acid is assessed against that mechanism.
What can I use instead of Polyhydroxystearic Acid?
Fungal-acne-safe alternatives in the same category include Acrylates Copolymer, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Ammonium Acryloyldimethyltaurate/VP Copolymer, Carbomer. Fungalscan suggests swaps like these automatically after an avoid or caution result.
Assessed using: Fungalscan methodology (C11-C24 rule).
This page is informational only and is not medical advice or a diagnosis. Fungal acne can resemble other skin conditions, and ingredient suitability varies by person and by formulation. Verdicts reflect community-reported data and malassezia lipid research, not a guarantee for your skin. Always patch test and consult a qualified clinician.