Millions of people around the world suffer from a self-mutilating and often painful addiction to biting their nails, which can be harder to quit than smoking cigarettes, but is often overlooked as a relatively benign habit, the Daily Mail reported.
The American Psychiatric Association is preparing to change the designation of nail biting from 'not otherwise classified', to 'obsessive compulsive disorder' (OCD) in its upcoming issue of the Diagnostic and Statistical Manual of Mental Disorders.
Habits that are commonly associated with OCD include repetitive hand-washing and hair-pulling. The disease is characterised by unreasonable thoughts and fears that lead to such repetitive behaviours.
The occasional chewed nail isn't an indication of the disorder, medical experts assure.
"As with hair pulling and skin picking, nail biting isn't a disorder unless it is impairing, distressing, and meets a certain clinical level of severity," said Carol Mathews, a psychiatrist at the University of California, San Francisco.
"That is not the vast majority of nail bitters," the paper quoted her as telling NBC News.
Nail chewing is considered severe when the habit becomes destructive