Sesame, or Sesamum Indicum, is an annual plant native to India that has been cultivated for nearly three millennia. From its seeds, it is possible to obtain a vegetable oil that exhibits a high oxidative stability. The sesame oil possesses moisturizing, anti-inflammatory, and antioxidant properties, making it a favored ingredient in haircare formulations. Its high fatty acid content notably strengthens the structure of the hair fiber and promotes its impermeability. Sesame oil also combats oxidative stress, which is harmful to the scalp and hair fibers.
In the quest for a natural method to darken their hair without causing damage, many individuals are turning to vegetable oils. Among these, some are wondering if sesame oil could be an option, due to the black color that some of its seeds can have. Indeed, depending on the variety, sesame seeds can be white or black. The color of the latter primarily comes from the anthocyanins they contain, flavonoids with pigmentation properties.
Indeed, hair pigmentation is due to melanin, a pigment synthesized in varying amounts by melanocytes. The higher the amount of melanin produced, the more intense and dark the hair pigmentation. The type of melanin synthesized also matters. There are two types: eumelanin is associated with dark-colored hair and pheomelanin results in blonde to red hair. In summary, it's the quantity and ratio of eumelanin and pheomelanin produced that determine hair color. Even though the application of sesame oil provides numerous benefits to the hair, it cannot influence this ratio and it does not have an immediate darkening effect either.
Note : Studies in vitro suggest that sesame oil could slow down the appearance of white hair by stimulating the activity of tyrosinase, the enzyme that catalyzes the transformation of tyrosine into melanin. It could thus help to preserve the natural color of the hair, without however changing their pigmentation or darkening them.