Snack Time

5 Research-Backed Reasons People Bite Their Nails

Nibbling on fingernails is a lot more than an acquired taste, research confirms.

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Why do people bite their fingernails? It’s still a matter of some scientific debate, but studies have shown that nail biters are far more than just shitty back-scratchers. Here’s what we know about nail biting:

Freud Thought It Was About Sex (Of Course)

Sigmund Freud initially thought that nail biters suffered from “oral receptive” personality disorder, due to excessive breastfeeding during infancy. Along with chewing on nails, those afflicted would have an oral fixation with other objects and be big fans of oral sex. Like most of Freud’s theories, this has been debunked more or less solely on the grounds that, however we may wish it, everything cannot be about boning. Besides, there’s no scientific evidence that nail biters are any more (or less) generous lovers.

Nail Biting Has Been Linked With Psychiatric Disorders

Excessive nail biting appears in the current Diagnostic and Statistical Manual of Mental Disorders as a symptom of Obsessive Compulsive Disorder, along with other habits like skin picking and hair pulling. A number of experts disagree with the American Psychological Association’s stance, but a literature review suggests that up to 80 percent of children with psychiatric disorders are also nail biters. We’re not saying one causes the other, but it certainly seems that the two conditions co-occur.

Nail Biters Are More Likely to Be Perfectionists

If a psychiatric condition does not cause people to bite their nails, perfectionism might, according to one study. When participants were shown movies meant to incite stress, such as footage of a plane crash, those who had previously scored highest on levels perfectionism chewed their nails more than others. So don’t worry too much about your own nail biting—could be that, as a perfectionist, it’s your only flaw.

Nail Biters Could Just Be Bored and Frustrated

By comparing four different nail-nibbling scenarios — being left alone (boredom), being left to solve difficult math problems (frustration), being in continuous conversations, and being reprimanded for nail biting, researchers found that bored and frustrated people bite their nails most. So, if you’re a nail biter who is not a perfectionist, and not suffering from a psychiatric condition, try getting out more. A simple change in company could bring the white back to your fingernails.

Nail Biters Are Young — At Least at Heart

Although scientists are mostly divided about what causes nail-biting, there is somewhat of a consensus. The younger you are, the more likely you are to bite your nails. Nearly half of adolescents bite their nails, according to one study, and upwards of 60 percent chewed them in childhood. Scientists suspect that most children grow out of this habit. So if your kids are chomping on their fingers, don’t worry too much.

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