Like to bite nails may be caused by the following aspects: 1, the cause of behavior habits, many people especially from children onwards nail biting. As a bad habit, it is possible that it is not well corrected from childhood, and it is difficult to correct when it has been kept in existence down after growing up. This time as a bad behavior habits, must be found after the rush to stop, and actively divert attention, and eventually control behavior. 2, there may be deep inside the tension, anxiety, both children and adults, in the tension, anxiety will have subconscious actions, such as accompanied by picking hands, rubbing hands, rubbing the corners of the clothes, or bite finger nails and other issues. If the behavior of nail biting occurs with tension, anxiety, worry, depression, you should actively treat the primary negative emotion problem symptomatically. 3, there are also some people who may be caused by physical illness or compulsive behavior and other psychological disorders, whether it is a physical illness or a psychological disorder, you need to treat the primary disease. For example, some people do have problems with OCD, repeatedly picking and biting their nails, a behavior that has become so serious that they even break the skin of their hands and bite the blood, but they still can’t control themselves. When you understand that you can stop doing this, but you can’t control it, it is very dangerous and must be treated actively, such as taking sertraline, venlafaxine, fluvoxamine and other drugs for anti-compulsive treatment. The above reasons are the more common ones.