Health. Can hair suddenly turn white due to stress or illness?

When it comes to sudden whitening of hair, two famous examples come to mind. The first, from across the Channel, concerns Sir Thomas More. Sentenced to death for high treason, his tonsure turned white the night before his execution in 1538.

The same effects apply to the French version of this story: in the days following her escape from Varennes, Queen Marie-Antoinette is said to have experienced a sudden whitening of her hair.

Two legends so deeply rooted that "sudden canities" (as the phenomenon is called) is more commonly known as "More's Syndrome" or "Marie Antoinette Syndrome." But what does science say about it?

Why does hair turn white?

Hair that turns gray and then white is a development associated with advancing age (even if we are not all equal when it comes to this phenomenon).

In this color change process, melanocytes, specialized cells, inject melanin into cells containing keratin. That is, in the skin, hair, and nails. As we age, melanin production declines. This causes hair to turn gray and eventually white.

The most commonly accepted reason is that Marie Antoinette or Thomas More must have experienced such stress before the axe fell that their hair suddenly turned white. A study published in 2020 in the journal Nature validates this hypothesis.

According to Harvard University researchers, severe stress or imminent threat activates the sympathetic nervous system, which may cause permanent damage to pigment-regenerating stem cells in hair follicles.

More or less validated hypotheses

But science remains in search of a definitive answer, and so other hypotheses have been put forward.

The first of these, and perhaps the most trivial, was put forward by British researchers in a 2008 article published in the Journal of the Royal Society of Medicine . Both Marie Antoinette and Thomas More were imprisoned for many months. They would then no longer have had access to their… hair dye. Thus, when it came time to reappear in public for execution, their natural hair color would have resurfaced.

Another explanation, according to these researchers: selective alopecia areata, an autoimmune disease that only attacks pigmented hairs, causing them to fall out. " Consequently, the patient only has white hair, creating an illusion of hair changing color ," the authors suggest.

Another autoimmune disease, vitiligo, from which former Prime Minister Edouard Philippe suffers. In the case of hair or beard, we more readily refer to it as "leukotrichia." But to the point of a mane turning completely white overnight is a bit... far-fetched.