Combatting the skin's oxidation process, which notably contributes to the exacerbation of skin ageing, has been a primary concern in recent years. Contrary to popular belief, olive oil, aside from its nourishing and soothing properties, also possesses antioxidant activity. Read on to discover if olive oil truly has an anti-radical action on the skin.
Olive oil for its antioxidant action?
Summary
Published on February 7, 2025, by Marie, Scientific Editor — 6 min of reading
Themes:
Olive oil, a vegetable oil rich in antioxidant molecules.
The olive oil is a vegetable oil that harbours numerous benefits for health and skin. Besides its moisturising, nourishing, anti-inflammatory, and antibacterial virtues, this vegetable oil is also surprisingly mentioned several times for its antioxidant activity, which would come from its bioactive compounds.
The phenolic compounds of olive oil, good antioxidants.
Olive oil is composed of various phenolic compounds, which act to mitigate the damage caused by excessive production of free radicals. It's worth noting that these unstable compounds develop following exposure to external aggressors, such as UV rays, pollution or tobacco. They are capable of inducing oxidative stress, causing damage to the DNA strands and proteins within the body.
Among the polyphenols found in olive oil are hydroxytyrosol and oleuropein, one of its derivatives. In 2001, a study conducted by ALMEIDA and his team evaluated the antioxidant activity of hydroxytyrosol and oleuropein by measuring their ability to neutralise the DPPH free radical. The researchers determined the necessary concentration of each compound to reduce the quantity of DPPH by 50% (EC50) after 15 minutes and 250 minutes of exposure in the same environment. The results, presented below, highlighted a strong antioxidant activity for these two molecules.
| Antioxidant | EC50 after 15 minutes | EC50 after 250 minutes |
|---|---|---|
| Hydroxytyrosol | 0.19 | 0.099 |
| Oleuropein | 0.22 | 0.12 |
Concentration of antioxidant required to halve the concentration of DPPH in the medium (in mol, antioxidant / mol, DPPH).
Adapted from: ALMEIDA M. & co. Comparative study of the antioxidant activity of hydroxytyrosol acetate and other polyphenols found in olive oil. Journal of Agricultural and Food Chemistry (2001).
Furthermore, additional studies have shown that oleuropein has an antioxidant activity superior to that of a well-known antioxidant: butylated hydroxytoluene (BHT). It reduces oxidative stress by neutralising free radicals through electron transfer. This action is primarily attributed to the hydroxyl groups presented by oleuropein.
These phenolic compounds also help to slow down the rancidity of the vegetable oil of olive, thus promoting its preservation over time.
The hydrocarbons found in olive oil exhibit antioxidant activity.
Olive oil also contains hydrocarbons, such as squalene and the β-carotene. Squalene has the ability to strongly attach itself to the hydrophobic part located between the two lipid layers of the bio-membrane, where the risk of lipid peroxidation is the greatest. Here, it exerts antioxidant properties that help to combat lipid peroxidation. This is an oxidative process during which free radicals attack the lipids of cell membranes, leading to their degradation and the formation of toxic compounds.
With regard to the β-carotene found in olive oil, it is a carotenoid responsible for the oil's pigmentation, but also possesses antioxidant properties. The double bonds it contains allow it to interact with free radicals and singlet oxygen, in order to neutralise them, thereby protecting cellular organelles from oxidative stress.
The presence of various antioxidants in olive oil could enable this botanical extract to combat oxidative stress and its harmful effects on the skin.
An antioxidant activity unique to olive oil?
Despite various studies conducted on the antioxidant activity of its components, the antioxidant action of olive oil as such, however, has not been the subject of scientific research at the moment. However, a study has been conducted on the effect of olive oil on photocarcinogenesis, that is, the induction of cancer through the transformation of cells under the effect of UV exposure.
The study conducted by ICHIHASHI and his team focused on the effect of olive oil on photocarcinogenesis in mice exposed to UVB radiation. For this purpose, the mice were divided into three groups of 15: (1) control group, (2) group where olive oil was applied before exposure, and (3) group where olive oil was applied after exposure. After irradiation with UVB, the number of tumours per mouse was counted. The averages obtained for groups 1, 2, and 3 were 7.33, 6.69, and 2.64 respectively. It would thus appear that the prior application of olive oil had a photoprotective effect. The scientists hypothesise that olive oil contributes to delaying the initiation stage of the p53 protein, which is responsible for the generation of carcinoma. However, further analyses would be necessary to fully elucidate this mechanism.
These data allow us to hypothesize about the antioxidant power of olive oil. However, at present, this has not been demonstrated in direct scientific studies.
Sources
ICHIHASHI M. & al. Protective effect of topically applied olive oil against photocarcinogenesis following UVB exposure of mice. Carcinogenesis Integrative Cancer Research (2000).
ALMEIDA M. & al. Antioxidant activity of hydroxytyrosol acetate compared with that of other olive oil polyphenols. Journal of Agricultural and Food Chemistry (2001).
VIOLA M. & al. Virgin olive oil as a fundamental nutritional component and skin protector. Clinics in Dermatology (2009).
RIBEIRO H. & al. Investigations of olive oil industry by-products extracts with potential skin benefits in topical formulations. Multidisciplinary Digital Publishing Institute (2021).
