Whitening of hair – Is it really due to stress?

When talking about sudden bleaching of the hair, two famous examples come to mind. The first, on the other side of the Channel, concerns Sir Thomas More. Sentenced to death for high treason, he saw his tonsure turn white the night before his execution in 1538. hair.

Two legends so well anchored that “canities sudden” (this is the name of this phenomenon) is more commonly called “More’s Syndrome” or “Marie-Antoinette’s Syndrome”. But what does science say?

Why does hair turn white?

Hair that turns gray and then turns white, this is an evolution associated with advancing age (even if we are not all equal in the face of this phenomenon).

In this process of color change, it is the melanocytes, specialized cells, which inject melanin into the cells containing keratin. That is to say on the skin, hair and nails. As we age, the production of melanin decreases. What makes the hair gray and ultimately white.

A question of stress?

The most commonly accepted reason lies in the fact that Marie-Antoinette or Thomas More must have known, before the ax fell, such a state of stress that their hair would suddenly turn white.

A study published in 2020 in the journal Nature indeed validates this hypothesis. According to Harvard University researchers, strong stress or an imminent threat activates the sympathetic nervous system, which would cause permanent damage to the pigment-regenerating stem cells in the hair follicles.

Hypotheses more or less validated

But science is still searching for a definitive answer. Thus, other hypotheses have been made.

The first of them, probably the most trivial, was issued by British researchers in an article dating from 2008 and published in the Journal of the Royal Society of Medicine. Marie-Antoinette and Thomas More were both imprisoned for many months. They would then no longer have had access to their… hair dye. Thus, when reappearing in public for the performance, their natural color would eventually resurface.

Another explanation, still according to these researchers: selective alopecia areata, an autoimmune disease that would only attack pigmented hairs, causing them to fall. ” As a result, the patient only has white hair, creating an illusion of color-changing hair. “say the authors.

Another autoimmune disease, vitiligo, from which former Prime Minister Edouard Philippe suffers. In the case of hair or beard, we speak more readily of “leukotrichia”. But from there to the mop of hair turning completely white in one night, it’s a bit… far-fetched.