32. Nervous Habits
Ah, the quintessential habit. The poster boy of bad habits. Biting your nails. There’s a reason it’s the first one that ever comes to mind when talking about bad habits people might have. Nailbiting is a common and unhealthy thing to do, bad both for your teeth and for your nails.

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Most commonly a habit of children, it is something that can stem as a nervous tick (much like teeth grinding and other things), and it’s a hard habit to kick once you’re stuck with it. There is apparently even a special kind of nail polish that tastes awful to help people trying to get rid of it.