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: 

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    Broken, chipped or cracked teeth

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    Misaligned front teeth

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    Worn tooth enamel

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    Damaged or shortened roots

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    Inflamed gums

Nail biting by age:1

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    7-10: Up to 33%

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    10-19: 45%

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    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:

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    Set small, realistic goals, as it may take time to completely break the habit, especially for children.

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    Try to avoid or help your child avoid the nail biting triggers you’ve identified.

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    Engage in stress-busting activities like exercise.

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    Trim nails short.

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    Keep hands busy with a stress ball or toy.

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    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.

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