Sometimes, we see some people reading books while biting (咬) their nails(指甲). We may think it is a kind of behavior(行为) that means they are focused(专心的). But in fact, it is more than that and science has proved it.
Nail biting can begin at an early age. According to the BBC, up to 45 percent of teenagers bite their nails. There
is not an exact answer to explain why people bite their nails. But most commonly,nail biting is said to be a nervous habit. It is done because of stress, boredom or excitement.
What's more, scientists found that people with higher levels of intelligence(智力) are the ones who start biting their nails at an early age. They believe that compared with common people, those with higher levels of intelligence may feel higher levels of stress more easily. This habit is bad for the biters. It can give them red or sore fingertips. And long-term nail biting can affect how our nails grow.
But don't worry! There are many ways to stop biting your nails. First, keep your nails clean. The more you focus on taking care of your nails, the less likely you are to start biting them again. Also, when you feel stressed, try to relax. Doing exercise or having a warm bath both help.