Why shouldn't I bite my nails?

OK, we're back with the low down on the negative side effects of nail biting. Many of you might've heard and/or believed that nail biting gives you stomach worms. My grandmother certainly scared the nail biting out of me by telling me old wives' tales about little boys who bit their nails and died with an nest of worms in their stomachs. Ew. Thankfully, there is no evidence to suggest that this is true. Sure, sure, absence of evidence is not evidence of absence, but the lack of evidence isn't for lack of trying. So, rest assured nail biters, you won't be filled with these thanks to your nail biting:



But don't get your hopes up. It's not all cotton candy and other nice, harmless things. Most people are convinced that nail biting is unsanitary, and they're right. A study published this year found that nail biters carried more potentially harmful bacteria - including E. Coli (which is harmful when it's in the wrong place) - in their mouths than non-nail biters.



There's more, of course. Dentists have been complaining for years that nail biting causes gum damage, inflammation, and infection. Nail biters often scratch their gums, and leave harmful bacteria in the wounds. The effects can be, and often are, painful.



Thirdly, nail biting has also been linked to the inflammation and infection of the fingers and fingernails. In its milder manifestations, you might just experience slight swelling of the finger tips (and the accompanying soreness). However, in some cases, the fungal infections might can get really nasty. Plus, they're contagious. Jeepers.



Now, our nod to evolutionary psychology: Nail biting reduces reproductive fitness. It's common knowledge that people find nail biting unattractive. Most people perceive the habit as a sign of nervousness, and that's rarely a good trait to portray. So...your nail biting habit might well render you mateless! It's a pity that there's no actual data on this, so no one knows if nail biting actually does reduce reproductive fitness, but it's a cool idea.

Well, that's all for the nasty effects of nail biting. Stay tuned for our homage to Positive Psychology: What are the benefits of having nice, unbitten nails?