Oleic Acid

INCI: Oleic Acid
Also known as: Omega-9
BarrieremollientbotanicalModerate evidencePregnancy safe
65
Skinlumis Rating
Comedogenic
2/5
Irritancy
1/5
Best applied
Both
Effective range
0.5%–10%
How It Works

A monounsaturated fatty acid that softens skin but penetrates more readily, higher penetration enhancer + higher irritation potential.

Disrupts stratum corneum lipid packing slightly, enhancing penetration of other actives, also can sting compromised skin.

pH Range
4.0–7.0
Benefits
  • Softens skin
  • Penetration enhancer
  • Mature-skin emollience
Proven For

What the evidence supports.

Mature dryness
Best For
  • All skin types
Avoid If
  • Acne-prone (in high %)
  • Severely compromised barrier
Layering Order
7/10

Later treatment or moisturiser step.

Max Safe Concentration
100%

Concentration range in well-formulated products: 0.5%–10%

Seasonal Use

Year-round.

Nutrition Connection

Olive oil, avocado, almonds.

Skin Signals When You Need It

No specific deficiency signals tracked for this ingredient.

For Estheticians & Professionals

Reserve for mature/dry; risky in acne-prone or atopic skin.

Clinical Evidence

The research behind Oleic Acid.

3 peer-reviewed studies

Every claim on this page traces to published research. Findings below are drawn from randomized trials and systematic reviews, each links to the study on PubMed.

Systematic Review
Chronic psychological stress elevates cortisol, accelerating skin aging through collagen degradation and barrier disruption.
Chen Y, Lyga J
Inflammation and Allergy Drug Targets, 2014
View Study →
Randomized Controlled Trial
Nano-hyaluronic acid significantly improved skin hydration and elasticity after 8 weeks.
Jegasothy SM, Zabolotniaia V, Bielfeldt S
Journal of Clinical and Aesthetic Dermatology, 2014
View Study →
Randomized Controlled Trial
Ceramide-dominant emollients improved skin barrier function by 63% within 6 weeks.
Draelos ZD, Ertel K, Berge C
Cutis, 2006
View Study →
Pairs Well With
SqualaneVitamin E
Conflicts With

No flagged conflicts. Still, patch-test new actives.

Your Skin Compatibility

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