Nail-biting is a stress removing habit adopted by many children. It is done when they are nervous, stressed, hungry or bored. All of these situations have a common phenomenon, and that is anxiety. It can sometimes be a sign of an emotional or mental disorder.

Most cases of nail-biting are seen between the ages of 4 and 6 years; stabilize from 7 to 10 and increase considerably during adolescence. 1

Consequences 1

  • Swallowed bitten-off nails can cause stomach infection.
  • Nails are seldom clean, and various diseases can be transmitted.
  • Nail-biting children are at risk of dental ill-health.
  • After adolescence, nail-biting is usually replaced by the habit of lip "pinching," chewing of pencils or other objects, nose scratching or hair twirling. In adults, it is substituted with smoking or gum chewing.

General prevention strategies 1,2

  • Nails should be well-trimmed.
  • Nail decorating (in girls) may prevent biting if it fits within the family culture and values. Children might apply bandages to their fingers to make their friends believe they have injuries.
  • If nail biting is a habit for you, stop it first or at the same time as your child (making it a competition may make it more motivating and fun).
  • Keep your child and their hands busy.
  • Teach your child effective ways to manage stress like deep, slow breathing, squeezing their muscles tightly and slowly relaxing them, as well as doing mindfulness activities.
  • Educate them, stimulate good habits and develop conscious awareness. No other way is more efficient, intelligent and satisfactory to stop the habit.

Habit Reversal Training (HRT)2

HRT is a research-based approach to treating all kinds of habits, including nail-biting.

  • Step 1: Increase your child's awareness of biting their nails 
    • Put something on their nails (bandages or gloves). These strategies are designed only to realize that they are biting their nails, not to stop them from doing it.
  • Step 2: Replacement behaviour – Have them do something else with their hands
    • Ask them to pick something or hold something for you.
    • Have them do something with their hands that they cannot do while biting nails (sit on their hands, hand actions or do arm movements).
  • Step 3: Build and Maintain Motivation
    • Use a reward system. Set a timer and give your child one point if they are able to go the whole time without biting. They can then use those points to buy rewards (screen time, dinner or movies).


  1. Sachan A, Chaturvedi T P. Onychophagia (Nail biting), anxiety, and malocclusion. Indian J Dent Res 2012;23:680-2
  2. Cody Hostutler. Nail Biting Prevention and Habit Reversal Tips: How to Get Your Child to Stop. Nationwide Children's Hospital.