The benefits of sunflower oil for the skin?

The sunflower oil contains high levels of linoleic acid (44 - 72%), an omega-6 fatty acid naturally present in the skin's sebum. Due to its high concentration, sunflower oil has emollient benefits. Indeed, it helps to improve the skin's natural barrier function and to enhance its ability to retain moisture. It thus helps to keep the skin hydrated, and prevents it from becoming dry and flaky.

A small study conducted with 19 volunteers, which compared the benefits of topically applied sunflower oil to those of olive oil, revealed that sunflower oil was more effective in enhancing skin hydration and maintaining the integrity of the skin's outer layer. Thus, good skin hydration can help prevent dry skin and associated symptoms, such as itching. Sunflower oil can then soften the skin and improve its texture.

Furthermore, sunflower oil is easily absorbed by the skin and does not leave a greasy residue, making it perfect for individuals with oily or combination skin, in addition to being non-comedogenic.

Sunflower oil is particularly concentrated in vitamin E (around 40 mg per 100 g), a popular fat-soluble antioxidant that helps to protect skin cells from oxidative damage caused by free radicals. Indeed, these unstable molecules are associated with a wide range of issues, from cancer to the acceleration of the skin ageing process, through to hyperpigmentation.

Besides nuts, spinach, whole grains and olive oil, sunflower oil is one of the richest sources of Vitamin E.

Although many other factors may contribute to the ageing process, sunflower oil could potentially help to prevent and minimise the signs of ageing, even though these claims are not, however, supported by scientific evidence. Nonetheless, the best strategy for preventing wrinkles is to limit exposure to direct sunlight and to wear a broad-spectrum sunscreen.

In addition to Vitamin E, sunflower oil also contains other antioxidants, such as selenium, phenolic acids (hydroxybenzoic acid) and flavonoids (rutin).

Several studies have reported that sunflower seeds possess antibacterial activity. They are believed to be capable of inhibiting the growth of microorganisms by increasing the permeability and fluidity of the cytoplasmic membrane, which causes its lysis. Indeed, they contain secondary metabolites (phenolic compounds and linoleic acid) that combat certain bacteria, such as Staphylococcus aureus, Streptococcus uberis, Propionibacterium acnes, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis and Micrococcus luteus. However, in vivo studies should be undertaken to confirm the current in vitroresults.

A small animal study also demonstrated the beneficial effects of applying sunflower oil to the skin on the healing of open wounds. Indeed, this study was conducted on 18 young male lambs, which were divided into three groups based on the duration for which they were observed post-operatively (7th, 14th and 21st day). On each lamb, two superficial thoracic wounds of 4 cm2 were surgically created. While one of the wounds was treated with pure sterilised vaseline, the other was treated with sunflower oil high in linoleic acid (65%).

The study demonstrated that the topical application of sunflower oil has enabledthe acceleration of the healing process on the 7th and 21st days by reducing the wound surface area, which is an increase in wound contraction. Furthermore, the results highlighted an increase in the development of granulation tissue on wounds treated with sunflower oil with a high concentration of linoleic acid. The epidermis of the treated wounds was completely recovered compared to the control wounds. This present study suggests that sunflower oil containing a high concentration of linoleic acid may be indicated as an alternative therapy for wound healing.

Sunflower oil is also believed to have anti-inflammatory properties, which could help to reduce redness, inflammation, and itching, and soothe irritated skin when applied topically. This is thought to be due to its high content of essential fatty acids, particularly linoleic acid. These would reduce inflammatory markers and mobilise the cells of inflammation. Moreover, its high concentration of linoleic acid helps to maintain the integrity of the skin barrier. A compromised barrier can lead to inflammation and redness. Furthermore, as it hydrates the skin, sunflower oil can provide temporary relief from irritations.

Studies have even established a link between topical sunflower oil and the reduction of psoriasis symptoms. In 2021, a study was conducted by POLICARPIO B. O. and his team in a double-blind, placebo-controlled manner, involving 51 patients suffering from psoriasis with mild to moderate plaque, who were treated either with sunflower oil and a placebo cream, or with a betamethasone valerate cream (local corticosteroid) and a placebo oil, or with a betamethasone valerate cream and sunflower oil, for eight weeks. After just four weeks, they noticed an improvement in psoriasis in the group treated solely with sunflower oil.

According to the same study, the linoleic acid found in sunflower oil is responsible for the anti-inflammatory effects in lesioned skin as mentioned above. Indeed, this unsaturated fatty acid would induce the inhibition of the NF-κB pathway involved in the inflammation process, thereby reducing the production of pro-inflammatory cytokines such as TNF-α. The correlation between the application of sunflower oil and the clinical manifestations of atopic skin suggests that sunflower oil could be useful in soothing certain skin conditions. However, further research is needed to confirm these findings and support the use of sunflower oil as an anti-inflammatory.

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