Olive oil, squalane and sunflower: what the studies say
By Jeremy Fain, founder of Restelys. Updated 17 October 2026. 4 sources cited.
Not all plant oils are equal for the skin. One study even showed that a very popular oil could weaken the skin barrier.
Olive oil has an excellent image. Yet a study in adults showed that applying it repeatedly for four weeks weakened the skin barrier, while sunflower oil preserved it. The cause is its high oleic acid content.
That is no reason to give up on the olive. Squalane, extracted from olives and then stabilised, is an emollient close to our skin’s own lipids: it softens without greasiness and does not have this drawback.
These results shaped our choice: our specification excludes raw olive oil and uses olive squalane in the body lotion and the conditioner.
Sources
- Danby S.G. et al. “Effect of olive and sunflower seed oil on the adult skin barrier: implications for neonatal skin care”. Pediatric Dermatology, 2013.
- Huang Z.R., Lin Y.K., Fang J.Y. “Biological and pharmacological activities of squalene and related compounds: potential uses in cosmetic dermatology”. Molecules, 2009.
- Kim S.K., Karadeniz F. “Biological importance and applications of squalene and squalane”. Advances in Food and Nutrition Research, 2012.
- Lin T.K., Zhong L., Santiago J.L. “Anti-inflammatory and skin barrier repair effects of topical application of some plant oils”. International Journal of Molecular Sciences, 2017.
The studies cited concern the ingredient or the skin, not our finished products.
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