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    Biting your fingernails can harm your mouth

    People who bite their nails often try to quit because it’s hurting the appearance of their nails. But nail biting can also spread harmful bacteria, viruses and more from your fingers to your mouth. This can increase your risk of colds and other infections. The risk is particularly high in children because they have less developed immune systems than adults and may not always wash their hands properly.

    As a result, nail biting can also cause a host of problems to your healthy smile. When it comes to oral health, here’s how biting your nails can come back to bite you. 

    Nail biting can begin as early as age 3. 

    Oral health issues

    Nail biting can put a tremendous amount of pressure on your teeth. As a result, research points the finger at nail biting for potentially causing these problems in your mouth: 

    check-mark-green Broken, chipped or cracked teeth
    check-mark-green Misaligned front teeth
    check-mark-green Worn tooth enamel
    check-mark-green Damaged or shortened roots
    check-mark-green Inflamed gums
    check-mark-green Tearing of the gums
    check-mark-green Jaw pain
    check-mark-green Grinding or clenching of the teeth
    check-mark-green Damaged dental work
    check-mark-green Increased amount of bacteria in the mouth

    Nail biting by age:(1)

    check-mark-green 7-10: Up to 33%
    check-mark-green 10-19: 45%
    check-mark-green 20+: 5%

    Tips to stop biting your nails 

    For you or your child to stop biting your nails, it’s important to find out what triggers the behavior. Boredom and stress are the most common culprits. Be aware of when nail biting takes place, and make note of what you or your child is doing and how you’re feeling. Once you’ve increased your awareness, try these methods to stop biting:

    check-mark-green Set small, realistic goals, as it may take time to completely break the habit, especially for children.
    check-mark-green Try to avoid or help your child avoid the nail biting triggers you’ve identified.
    check-mark-green Engage in stress-busting activities like exercise.
    check-mark-green Trim nails short.
    check-mark-green Keep hands busy with a stress ball or toy.
    check-mark-green Occupy the mouth with healthy snacks like crunchy carrots and celery. 

    You may also want to consider applying a bitter-tasting nail polish to your nails or covering them with tape, stickers or gloves.

    Be aware that bitter nail polish and finger coverings are generally ineffective for children because those methods are seen as punishment. It’s important to avoid anything that will increase a child’s stress and frustration. Punishment often only increases their nail-biting behavior. Research shows that giving them encouragement, rewards, support and confidence is the best way to help them break the habit.

    If you or your child find it difficult to quit biting your nails, consult with your physician or dentist. In some cases, behavior therapy may be recommended to help break the habit.