Legend has it that the night before she was beheaded, Queen Marie Antoinette of France’s hair turned white overnight. It wasn’t the first recorded case in history. In the 16th century, Thomas More, who famously opposed Britain’s separation from the Catholic church, went through the same thing before his execution. So what was triggering this change?

Marie Antoinette Syndrome, also called Canities subita, is not a settled debate in the scientific community. Stories of it run rampant, but there are very few scientific case studies. Among these very few is a report of bombing survivors from World War II who suffered from the syndrome, but even that is disputed. In fact, some researchers have argued that we don’t know any mechanism through which this can happen.

In another relatively recent report from 1957, an American dermatologist witnessed a 63-year-old man’s hair turn white over just a few weeks. The man had fallen down some stairs. He also reported loss of hair, but not major bald patches; 17 months later, he had extensive vitiligo (pale patches on the skin) as well as grayed-out hair.

The syndrome (if it does exist) appears to be triggered by extremely high levels of emotional stress, which in turn, can lead to loss of pigment in the hair. This fits with existing research on natural hair graying, which researchers have found is triggered by stress — and remarkably, it is reversible (unless the body has lost the ability to produce melanin). But there have still been very few well-documented cases of Canities subita, and studies are few and far between.

The science of Marie Antoinette syndrome

When Neurologist Brown‑Séquard was 45 years of age, he unexpectedly discovered white hairs in some parts of his beard. He plucked them out, but after a few days, he discovered new white hairs. He kept repeating the process, and for the next 5-6 weeks, he would always find new white hairs in his beard, appearing seemingly overnight.

A 2013 medical review tells the story of Brown‑Séquard and 195 other cases. In the case of the neurologist, there was no apparent trigger, and the discoloration didn’t happen overnight (though it did happen very quickly). However, in the vast majority of cases, emotional distress appeared to be the main cause.

“Of the 196 cases in our collection, 126 were attributed to frightful or emotionally shattering experiences,” the study authors note.

“For example, in March 1923, a 62‑year‑old widow was injured and suffered extreme fright when she slipped and fell. She remained in the hospital for 3 months. The woman had dark hair, which measured 80 cm at the occipital region of her head. On the morning of the second day in hospital, the basal areas of the hairs of the frontal hemisphere of her head had turned white on a length of 1 cm. [..] On the last examination of the woman, performed 92 days after her release from the hospital, the basal whitening of her frontal hair was 10 cm and the occipital area of her head had turned entirely gray.”

Some cases were also linked to psychiatric disorders. In one particular case, a 13‑year‑old patient with severe mental disabilities who also suffered from apparent epileptic fits experienced episodes in which her hair lost coloration and then regained it back — which is consistent with recent research about the reversibility of some forms of hair discoloration.

“Her hair color changed repeatedly from a yellowish blond to a reddish‑golden color and back again. The reddish color lasted for 7 or 8 days, always correlating with periods of mental agitation. There was no alopecia, the possibility of hair dyes was excluded and several caregivers and physicians witnessed these repeated color changes. A similar case involved a 21‑year‑old woman who suffered from schizophrenia,” the researchers note.

However, some researchers don’t see Marie Antoinette syndrome as a stand-alone problem, but rather as an acute episode of diffuse alopecia areata — a type of spot baldness, in which hair is lost from some or all areas of the body.

However, this is far from a settled issue.

“Although no conclusive proof exists that rapid Canities can occur without concomitant alopecia areata diffusa, the sheer number of authenticated cases suggesting this call for a more systematic investigation of what factors may prompt loss of hair color. Such an investigation may provide new insights into the process of physiologic Canities,” the authors of the 2013 study conclude.

Untangling the science from the myth

So far, one thing is clear: Marie Antoinette syndrome is much more common in stories and myths than in real life. It’s a striking storytelling element, but it’s hard to distinguish facts from fiction. In fact, one study was dedicated to disproving the myth that Henry IV of France suffered from it.

If it is indeed a separate condition, it seems to be associated with stress — which would point towards an autoimmune condition. But a study on mice seems to disprove this hypothesis. The study found that stress caused white hair in mice even when the immune system was suppressed — thus ruling out an autoimmune response. The study concluded that the over-activation of the sympathetic nervous system (which triggers the fight or flight response) was responsible, by causing stem cells to stop producing pigment cells in hair follicles. However, as this wasn’t a huge study and it was on animals, more research is needed to draw stronger conclusions for humans.

In fact, one study suggests that historical accounts of Marie Antoinette syndrome are rather linked to alopecia areata or the washing of hair dye. But this doesn’t seem to be the case for at least some of the reported cases. So the science is not exactly set here, and there’s a fair amount of disagreement between researchers — part of which stems from how old and rare cases are.

Marie Antoinette syndrome has been historically linked to extreme stress. But while stress can cause premature gray hairs in time, it’s not clear if it can do so overnight (or within a few weeks). It may be linked with hormonal disruptions as well or some autoimmune condition, but at this time, there’s just not enough information to draw clear conclusions. Undoubtedly, researchers will continue to explore this syndrome and hopefully, we’ll soon get to the root of things.