What does it mean when they bite their lip?

In some cases, physical conditions can cause a person to bite their lips when they use their mouth for talking or chewing. In other cases, the cause can be psychological. People may bite their lip as a physical response to an emotional state, such as stress, fear, or anxiety.

Is lip biting a mental disorder?

While not specifically referred in the newest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), chronic lip biting falls under “other specified obsessive-compulsive and related disorders,” specifically under BFRB.

Why do I keep biting my bottom lip?

Many people do bite or chew on the insides of the lower lip or cheek, perhaps out of boredom or nerves. This habit is often initially prompted by a misdirection of the teeth that causes the person to mistakenly bite into the lower lip while chewing.