Black seed oil, a natural remedy against white hair?

The appearance of white hair, commonly referred to as canities, is often associated with a decrease in melanin production by melanocytes and a gradual reduction in their number. Depending on the individual, this natural process usually occurs around the age of 35. However, aging is not the only factor contributing to the onset of white hair. Genetics also play a major role, as well as prolonged stress or nutritional deficiencies.

Furthermore, the whitening of hair is accelerated by stress oxidative caused by prolonged exposure to UV rays or pollution. Indeed, at the scalp level, ROS (reactive oxygen species), free radicals, attack the stem cells of melanocytes and induce them into apoptosis. As a reminder, apoptosis is the process by which cells trigger their self-destruction. This reduces the population of follicles in the anagen phase, that is, the growth phase, by melanocytes, and therefore leads to a depigmentation of the hair. In addition, over time, the activities of the anti-apoptotic protein BCL-2 and the antioxidant enzyme catalase decrease, which facilitates the attack of melanocytes by free radicals and their apoptosis.

Theblack seed oil is a vegetable oil extracted following the cold pressing of black cumin seeds. Rich in saturated and unsaturated fatty acids, as well as active principles, it provides a multitude of benefits to the skin and hair. Its composition notably gives the black seed oil antioxidant, moisturizing, and anti-inflammatory properties.

The topical application of black seed oil can, to some extent, help to delay the onset of graying hair. However, it cannot reverse the effects on already formed white hair. To slow down the graying process, black seed oil utilizes thymoquinone, its active ingredient. This molecule works by protecting hair fibers and the scalp from oxidative stress caused by free radicals by upregulating the activity of certain antioxidant enzymes, such as superoxide dismutase (SOD), glutathione peroxidase (GPx), and also catalase. Thus, black seed oil is capable of protecting melanocytes, and preserving their melanin synthesis activity, which is essential for hair pigmentation.

Note : While the correlation between oxidative stress and hair graying has been scientifically established, no study on black seed oil has focused on its effects on canities. Thus, although the antioxidant properties of this ingredient seem interesting in fighting against the appearance of white hair, it is necessary to remain cautious.

• SEIBERG M. Age-induced hair greying - the multiple effects of oxidative stress. International journal of cosmetic science (2013).

• KIM B. & al. Black Cumin ( Nigella sativa L.): A Comprehensive Review on Phytochemistry, Health Benefits, Molecular Pharmacology, and Safety. Nutrients (2021).