I have no idea when I graduated from chewing on pencils to chewing on my fingers—maybe I always did both. Kids don't think about such things, and I didn't even realize I was doing it. But neither do most people with dermatophagia, the not-all-that-rare impulse to bite and, sometimes, ingest your own skin.
Though it's somewhat common, dermatophagia has rarely been described in medical literature, and it's something people don't talk about all that often, perhaps because they're embarrassed. But it's also because it's generally something that's fairly innocuous and doesn't require treatment.
The vast majority of people who chew on themselves don't ever seek professional help, most grow out of it, and it often doesn't really cause problems, other than perhaps making your fingers look gross.
over months the involved skin eventually becomes thick, callous like, and lichenified
"It is not as rare as the sparsity of case reports would indicate," father-son psychosomatic dermatologists Michael Scott Jr and Michael Scott III wrote in their 1997 description of the condition, published in the journal Cutis. "It is seldom mentioned in textbooks."
Specifically, the disorder is "a neurotic habit or compulsion to self-mutilate their skin or its appendages," with one's teeth.
When it is mentioned in medical literature, people who chew on their own skin (I have long since stopped) are often called "wolf biters," because that's exactly what wolves do when they're trapped or annoyed. In their paper, the Scotts suggested the term "dermatophagia," because, well, it's more scientific.
But even that distinction has its detractors. Dermatologists with the Walter Reed Army Medical Center suggested in a 2005 article in the Journal of the American Academy of Dermatology that dermatophagia, literally "skin eating" in Greek, gives the false impression that people are regularly eating the skin.
"Published reports of dermatophagia describe patients whose behavior consists solely of compulsive biting or gnawing their skin, but not actually ingesting it," Panagiotis Mitropoulos wrote in the journal. "Indeed, these patients developed a reactive thickening of the skin, not a wound, ulceration, or loss of skin."
Miropoulous proposed calling it "dermatodaxia," which means "skin biting."
No matter what we're calling it, it's clear from both photos of people with the disorder and online descriptions that some people do indeed eat tiny flecks of their own skin.
"It's a way of responding to stress, a way of relieving stress," Scott III told me in a phone interview. "We have some people who have done it for 20 years, they just keep at their life—it's not disfiguring most of the time."
Scott told me that most of his clients who have dermatophagia have come in for another disorder, and the skin biting came up as a separate issue. He says that, like me, most people with dermatophagia grew up biting their pencils in school and at some point switched to their skin. Most often, someone with the disorder is biting the area near their fingernails, their knuckles, arms, or "any accessible place on the body."
It's not always innocuous, either.
A redditor recently suggested that he hates "that sting when you know you've gone too deep and start bleeding."
"It can sometimes get so bad that it's painful," Scott said. "After such repetitive action over months the involved skin eventually becomes thick, callous like, and lichenified with loss or exaggeration of the normal skin markings or creases."
It's also terrible for the hair follicles in whatever area has been bitten.
Most commonly, however, things turn out just as they did for a totally normal 15-year-old boy described in a case study in Dermatology and Psychosomatics: "The boy's behavior was normal except for stubbornness, and his school performance was satisfactory," the paper said.
"In the course of a few months the nature of his condition was explained to the boy and he was instructed to consciously desist from biting his knuckles," it continued. "The boy is under follow-up and has almost given up his habit."
So, for you dermatophagists out there: It gets better.
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