Melanin provides color to both hair and skin. Each hair follicle houses two melanin reservoirs: one at the root base with active melanocytes, the other at the top with dormant ones. In every hair growth cycle, dormant melanocytes migrate downward to activate. Repeated cycles deplete this melanocyte stock, worsened by oxidative stress from UV rays, excessive heat styling, and genetics. Notably, canities (white hair) tends to appear later in Black and Asian hair types. Hair doesn't suddenly turn white overnight—it's an optical illusion from lacking melanin, which makes strands fragile, coarse, porous, and dull as pigments fade.
Gray hair isn't inevitable. Kérastase research labs have pioneered an antioxidant complex—ferulic acid, vitamins C and E, plus UV filters—in their Densifique Youth Serum (€80). It targets melanocyte preservation to delay graying. No repigmentation treatment exists yet, but Patrick Canivet, Technical Director at L'Oréal Professional Products, shares: "Research is progressing. In ten years, we could fully prevent gray hair." Watch this space. For now, coloring is the best option for grays.
