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Why is nail-biting so addictive? © Getty Images

Why is nail-biting so addictive?

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Otherwise known as onychophagy or onychophagia, the compulsion to chew your nails may just be a sign that you’re striving for perfection.

Asked by: Madison Hughes, Shropshire


There are plenty of theories for why people start nail-biting (or what doctors call ‘onychophagia’), including perfectionism and stress. And there’s also the Freudian notion that it’s to do with being stuck at the oral stage of psychological development! But as to why nail-biting is so addictive (20 to 30 per cent of us do it), there’s little research.

We can speculate that it is to do with its cost-free ease, practicality and relative social acceptability, and there’s the rewarding aspect of getting each nail just how you want it. On a positive note, childhood nail-biters are less prone to allergies, presumably because they’re exposed to more germs.


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Dr Christian Jarrett is a cognitive neuroscientist, science writer and author. He is the Deputy Editor of Psyche, the sister magazine to Aeon that illuminates the human condition through psychology, philosophy and the arts. Jarrett also created the British Psychological Society's Research Digest blog and was the first ever staff journalist on the Society's magazine, The Psychologist. He is author of Great Myths of The Brain and Be Who You Want: Unlocking the Science of Personality Change.


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