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Ol

Oleic Acid

Oleic AcidBarrier

A skin-softening fatty acid that feeds the yeast behind fungal acne.

What it does

The yeast behind fungal acne (small, itchy, same-size bumps) can’t make its own fatty acids and feeds on ones it finds on skin. A 1968 lab study found it grows on fatty acids from lauric acid up, but not on shorter ones. Oleic acid falls in that range, so it’s counted as a fungal-acne trigger at usual amounts.

The EU’s ingredient database lists it as an emollient (gives skin a soft, smooth look) and an emulsifier (helps oil and water mix).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗

The evidence, graded

expert consensusFungal acne is Malassezia folliculitis — an overgrowth of a yeast already living in normal skin flora, commonly mistaken for ordinary acne. In a culture dish the yeast grows only when fatty acids longer than C10 are added, because it cannot make its own. That is why Drop holds lipid-rich products back while you have this flagged. No source Drop has read tested an oil on skin, set an upper chain length, or showed squalane, MCT or mineral oil to be safe.Rubenstein 2014 · Journal of Clinical and Aesthetic Dermatology ↗

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Also known as

cis-9-octadecenoic acid

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