16 Disturbing Things Your Nails Reveal About Your Health

13. Gnawed Nails

Nail biting is a habit that affects 20 to 30% of Americans. Often it's a self-soothing habit that's more prevalent during times of high stress or anxiety. Most people grow out of it or are able to stop by using deterrents such as foul-flavored nail polish.

If a person can’t stop biting their nails, they may have a condition called onychophagia, which is considered a body-focused repetitive behavior (BFRB). People with other types of compulsive behavior are more likely to have onychophagia, as are people with ADHD, Tourette’s, or separation anxiety.