Oleic Acid

Omega-9 fatty acid found in many plants, including grape seed

Primary fatty acid found in olive oil

Used as a cleansing agent and texture enhancer

Has improved skin calming abilities when combined with other lipids

Oleic acid is a natural, monounsaturated omega-9 fatty acid found in many plants, including grape seed, olives, and sea buckthorn. It’s the primary fatty acid in olive oil and believed to play a role in this oil’s cholesterol-lowering benefits when consumed orally.

Interestingly, research has shown that topical application of oleic acid on its own or as olive oil can disrupt skin’s barrier; however, this effect was not observed when oleic acid was blended with other fatty acids and skin-beneficial ingredients.

On the upside, this kind of barrier disruption can enhance penetration of other ingredients naturally present in plant oils or in the product, so it’s not necessarily all bad (and, as we mentioned, not bad at all unless you’re applying pure oleic acid or straight olive oil to skin).

In another interesting twist, combining oleic acid with other lipids (fats) boosts its skin-calming ability, thus making oleic acid useful for reducing signs of dryness and sensitivity when used in this capacity.

In cosmetics, oleic acid is used as a cleansing agent and texture enhancer. It’s among the more stable unsaturated fatty acids and has a unique ability to preserve the effectiveness of more delicate ingredients such as antioxidants by helping to protect them from light and air degradation.

In hair care formulations, the use of oleic acid can help impart a healthy shine to hair.

The independent Cosmetic Ingredient Review panel has ruled oleic acid safe as used in cosmetics, where typical usage ranges from 1–10%.

Lastly, oleic acid is also naturally occurring in cosmetic ingredients stearic and palmitic acids.

See: Stearic Acid, Palmitic Acid