Why is nail-biting so addictive?

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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