Can Nigella sativa oil protect the skin from the sun’s UV rays?

Exposure to sunlight is one of the primary stressors for the skin.

Ultraviolet radiation, particularly UVA rays, penetrates deeply into skin tissues and contributes to the excessive production of free radicals. These free radicals damage cellular components, disrupt repair mechanisms, and promote inflammation, thereby contributing in the long term to skin aging and to certain skin diseases. To limit these effects, it is important to use sunscreen, whose effectiveness relies on UV filters capable of absorbing and reflecting the sun’s rays before they reach the skin cells.

However, some people express reservations about sunscreen filters and wonder about naturally derived alternatives. In this context, vegetable oils are sometimes mentioned, among which black seed oil, extracted from the seeds of Nigella sativa, also called black cumin. This oil is recognized for its richness in bioactive compounds, notably thymoquinone, and for its antioxidant and anti-inflammatory properties. The question then arises whether these characteristics might confer a protective role against the effects of sun exposure.

An experimental study examined the role of thymoquinone in UVA-induced skin damage. This work was conducted on human HaCaT keratinocytes, a widely used cell model. The cells were pretreated with thymoquinone, then exposed to UVA radiation. The researchers evaluated cell viability, apoptosis, markers of oxidative stress, inflammatory cytokines, and mitochondrial function.

The results demonstrated that thymoquinone could reduce UVA-induced cytotoxicity in keratinocytes.

Preconditioning has limited the accumulation of free radicals, attenuated the inflammatory response, and reduced mitochondrial stress–related cell apoptosis. From a mechanistic perspective, these effects appear to be associated with activation of the Nrf2/ARE pathway, a cellular antioxidant defense system, as well as inhibition of COX-2 expression, an enzyme involved in inflammatory processes. When this pathway was experimentally blocked or when COX-2 was activated, the observed protective effects disappeared, suggesting a role for these mechanisms in the cellular response.

These findings offer valuable insights into the antioxidant and anti-inflammatory potential of thymoquinone against UVA-induced stress, but they should be interpreted with caution.

This is a studyin vitro, performed on isolated cells, which does not allow concluding a direct protective effect of black seed oil against UV rays in humans. Furthermore, the study examined thymoquinone, present in low amounts within black seed oil (<1%). It is uncertain whether the thymoquinone concentration in black seed oil is sufficient to achieve this photoprotective effect.

Furthermore, a study conducted by MARTINIAKOVA and her team in 2021 examined the photoprotective capacity of various vegetable oils, including black cumin oil, by evaluating their sun protection factor (SPF). The authors measured both the SPF in vivo, according to the ISO 24444 standard, in an accredited laboratory in Prague, and the SPF in vitro using the Mansur spectrophotometric method. The values obtained were found to be particularly low.

These results clearly indicate that black seed oil does not have sufficient UV‐filtering capacity to provide effective sun protection. By comparison, it is generally recommended to use products with an SPF of at least 30 to limit the effects of UV rays on the skin. Black seed oil therefore cannot be considered an alternative to sunscreen filters. However, its antioxidant potential remains relevant. By helping to neutralize part of the oxidative stress induced by sun exposure, black seed oil can be viewed as a supplement within a skincare routine. It should not, however, replace sun protection, which alone can effectively block UV rays.

On its own, nigella oil cannot be considered a natural sunscreen. However, it can be an interesting complement to sunscreen due to its antioxidant properties.

• MARTINIAKOVÁ S & al. The real UVB photoprotective efficacy of vegetable oils: In vitro and in vivo studies. Photochemical & Photobiological Sciences (2021).

• LI L. & al. Thymoquinone, extract from Nigella sativa seeds, protects human skin keratinocytes against UVA-irradiated oxidative stress, inflammation and mitochondrial dysfunction. Molecular Immunology (2021).

• GUNADI J. W. & al. Role of Nigella sativa L. seed (black cumin) in preventing photoaging (review). Biomedical Reports (2025).