Baz Ratner / Reuters

Canities subita is the medical term for hair turning white overnight. The phenomenon is almost universally acknowledged as myth—but not entirely. A 2013 study in the International Journal of Trichology found 84 reports of "unusually rapid" adult hair-blanching in medical literature between 1800 and the present day. Of these, 14 were witnessed by a physician, and were not explained by the rate of follicle growth or any known medical conditions.

I am here to report an 85th case: my own. On the night of October 7th, 2013, while on a reporting trip in Dagestan, every coarse, dark hair over my upper lip turned pure, pigment-less white. They remain so to this day—wiry and strong as they’ve been since late puberty, but white like raw onions.

The lead author of the 2013 study, Michael Nahm, says mine is the 16th personal account he’s received of apparent canities subita since publishing the paper. A forestry scientist at the University of Freiburg, Nahm researches unexplained biological phenomena in his spare time. “All these accounts support the notion that sudden whitening does indeed happen,” he writes over email, “although we still don’t know how exactly it occurs. It remains an under-investigated phenomenon.”

It doesn’t help that the most famous accounts predate modern medicine, such as the apparent canities subita of Mary, Queen of Scots, before her beheading in 1587 at age 44. When the executioner held up her severed head to show the crowd, he let her wimple fall away to reveal short-cropped white hair. “It was not old age that had turned it white,” attested French nobleman Pierre de Bourdeille, who witnessed the decapitation, “but the troubles, misfortunes, and sorrows which she had suffered, especially in her prison.”

A 2009 paper in the Archives of Dermatology coined the phrase “Marie Antoinette Syndrome” for the sudden whitening of scalp hair, which the late queen herself attributed to her hardships amid the French Revolution. In June 1791, when a 35-year-old Marie Antoinette returned to Paris following the royal family’s failed escape to Varennes, she removed her cap to show her lady-in-waiting “the effect which grief had produced upon her hair,” according to the memoirs of the lady-in-waiting, Henriette Campan.  Though historians have since posited that Marie-Antoinette simply ran out of hair dye during her attempted flight and subsequent imprisonment, Campan insists in her memoirs: “It had become, in one single night, as white as that of a woman of seventy. Her Majesty showed me a ring she had just had mounted for the Princesse de Lamballe; it contained a lock of her whitened hair, with the inscription, ‘Blanched by sorrow.’”

True to the folklore, more modern instances of canities subita also seem to immediately follow intense stress or trauma. The British Medical Journal in 1902 reported the case of a menstruating 22-year-old woman whose pubic hairs turned white on the right side of her body after she witnessed “a woman’s throat being cut and the victim falling dead at her feet.” Her physician at the London Temperance Hospital writes that “menstruation was arrested, and the next morning the whole of the hair of the pubes on the right side was pure white, while that of the left remained dark. All the pigment of the right labium majus has disappeared.” Her periods returned after nine months; the pigment in her right-side pubic hair did not.

A 1915 Scientific American supplement notes that the hair of a 23-year-old French soldier at the Argonne front whitened in patches after he survived a mine explosion: “He was taken to the English hospital at Arc-en-Barrois, where on the following day he noticed, to his surprise, tufts of white hair on the left side of the head.” His other symptoms included “incessant twitching of the left eyelid.” His left side was where he was most badly bruised in the blast.

The circumstances of my own canities subita were more benign. Having flown into Dagestan from Moscow earlier that day, I was reclining in my ground-floor hotel room when prolonged gunfire erupted directly outside my window. The shots turned out to be celebratory, most likely a Dagestani wedding party. But I didn’t know that during the 15 minutes I spent cowering under my bed, covering my ears.

When the gunfire slowed enough for laughter and hooting to become audible, I crawled out from under my bed, smoked several cigarettes, and went to sleep. The next morning, while brushing my teeth, I saw that my previously brown lip-bristles had lost all color from root to tip.

My canities subita cannot be medically authenticated, since no doctors were around to see it. Nevertheless, I reached out last week to Des Tobin, a leading expert on cell pigmentation and director of the Center for Skin Sciences at the University of Bradford. Over the phone from Ireland, Tobin patiently explains why my account is logically impossible: “There are no living cells in the hair. Psychosocial stress can’t affect the hair fiber that’s already formed, it can only affect the fibers as they’re forming.”

He suggests that what I thought was canities subita may have been an occurrence of alopecia areata, a stress-linked autoimmune reaction that causes sudden hair loss. Because it often targets pigmented hair while leaving de-pigmented strands in place, this form of alopecia is the leading explanation for the appearance of sudden hair-whitening in people with salt-and-pepper locks. The pepper falls out, the salt remains.

I interrupt that my mustache is as thick as it’s ever been. And it was sparse enough before the incident that I would have noticed any white hairs that were already there. For good measure, and to demonstrate the extent of my Googling on the matter, I add that I have also not experienced any skin-whitening vitiligo, which sometimes accompanies the sudden appearance of white hair.

Tobin next inquires about my genetic background, my age, and the condition of my mustache at the time of the blanching. I was 30 years old in October 2013, I tell him, and inherited my hirsute upper lip from the Iberians on my father’s side. A salon professional had last depilated said upper lip roughly one week prior to the event, meaning the hairs were wispy, but present.

At the mention of my salon routine, Tobin points out that depilation itself can make hair more susceptible to blanching, by inflicting “microtrauma” on the follicles and rendering them more porous. “In rat studies,” he offers, “they showed if you pluck the rats’ whiskers, they grow white more quickly.”

For my whiskers to whiten all at once, Tobin says I would have had to be in direct contact with some external agent—a detergent used on the hotel’s sheets, perhaps. My years of upper-lip microtrauma and the resulting porosity of those follicles would make them more susceptible to being bleached, and would explain why no other hairs were affected.

If so, the stumper remains that the hairs are still white, nearly three years after the fact. “Whatever has happened managed to affect the melanocytes inside the root of the follicle, and caused them to shut down completely,” Tobin muses, referring to the skin’s pigment-producing cells. I offer to mail him some clippings from my mustache so he can analyze the hair shafts for himself. He politely declines and our phone-consult ends there.

Back in Freiburg, Nahm writes that he’s “open to ‘non-local correlations’ between mental states and bodily conditions that don’t follow traditional models of (biophysiological) causation.” The “non-local” stuff, which Einstein dismissed as “spooky action at a distance,” takes us into quantum entanglement theory and the idea that the conscious mind has more impact on the body than classical physics would allow. This interpretation of quantum theory is controversial and mysterious enough that I can’t say whether or not I’m open to it as an explanation for my blanched facial hair.

For now my canities subita remains a mystery, albeit a happy one. The white hairs are faint against my oatmeal-colored skin, and I was lucky enough not to be in any real danger while acquiring them. The only victims of my circumstance are the depilatory professionals of New York and London, who I visit far less frequently now than when my mustache grew in brown. As unexplained medical conditions go, canities subita is a fine one to have.

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