The white hair They are considered an inevitable mark of aging. However, science is beginning to dismantle this belief: graying does not depend exclusively on age, but on specific biological processes that affect the functioning of the cells responsible for hair color.

According to a study published in the Nature magazinespecialists from the Grossman School of Medicine (New York University) detected that melanocyte stem cells (McSC) stop producing the protein responsible for hair pigmentation when they remain immobile, a mechanism that could be behind the appearance of gray hair.

This finding not only changes the view on how this phenomenon originates, but also opens the possibility of reversing it if these cells manage to recover their function and mobility. Will it be possible to reverse gray hair in the not too distant future?

Gray hair: a scientific study reveals why they appear and opens the door to reversing them

From tests with mice, the researchers observed that, in normal situations, McSCs move between compartments within forming hair follicles. These spaces allow stem cells mature and obtain the protein necessary to become pigment cells, which guarantees the color of the hair during its growth.

Over time, these cells alternate between different maturation states as they migrate from one compartment to another, a distinctive behavior of McSCs. However, under certain circumstances, McSCs may be retained in the bulge compartment of the hair follicle.

It is in this place where WNT proteins activate these cells to regenerate as pigment cells. When immobilized, they lose that regenerative capacitythey stop producing pigment and, as a result, gray hair appears.

“These findings suggest that the mobility of melanocyte stem cells and their reversible differentiation are key to maintaining healthy and colored hair,” he explained. Mayumi Itoprincipal investigator of the study.

Would it be possible to reverse gray hair?

The mechanisms discovered by scientists open an encouraging possibility: that the immobilization of melanocyte stem cells also occurs in humans. If this is confirmed, a strategy could be developed to reverse or prevent gray hair by reactivating the movement of these cells between compartments of hair follicles, a key process for pigment production.

The study showed that cells that remain mobile retain their ability to give hair color, but this system deteriorates with aging, which explains why gray hair appears over time.

Furthermore, research from Harvard University determined that stress does not directly cause graying, but rather accelerates the aging of hair follicles by increasing the hair regeneration cycle.

According to the New York University team, the melanocyte stem cell system fails earlier than other adult stem cells, triggering pigment loss. The next step will be to find a way to reactivate the movement of these blocked cells so that they produce pigment again, which could open the way for reverse gray hair.