This post may contain affiliate links that support the site at no cost to you.

You already know that nail biting is bad for your nails. But did you know it’s also pretty bad for your teeth? 

If you came here looking for a reason to kick the bad habit and stop biting your nails, you came to the right place. Nail biters – read on and learn why and how to quit. 

Why do people bite their nails?

Nail-biting is mostly considered a nervous habit or coping mechanism. When it is mild, it is generally only damaging to the nails. Nail biters tend to bite their nails down to the fingertip, which is unsightly and often uneven.

For more serious nail biters, their bad habit might be constant or compulsive, and it might extend to chewing on the cuticles or nail beds as well. This is where permanent damage to the nails, ingrown nail, and infections are likely.

But in addition to the possible damage to your fingers, nails and overall health, there’s also significant possible damage to your teeth and oral health.

What does nail biting do to my teeth? 

What seems like a harmless nervous habit is actually a pretty serious problem for your teeth! 

When you bite your nails, you’re increasing your risk of:

• Bad breath
• Cavities
• Gum disease and gingivitis
• Tooth grinding
• Jaw pain/TMJRapid tooth decay or tooth wear
• Teeth shifting 
• And overall illnesses

Now, let’s look at each of these to understand why nail biting is such a serious problem. 

Bad breath

If there’s one problem that is likely to get people to start taking nail-biting seriously, it’s bad breath. Unlike some of the other items on this list that are damaging to your future health, bad breath is immediate, and so embarrassing! Most people suffering from bad breath will do anything to improve it. 

Just like your gut has a microbiome, your mouth does too (the “oral microbiome”). When you put your dirty nails into your mouth, you’re introducing harmful bacteria that can grow in your mouth. When odor-causing germs are able to take root in your mouth, you can get recurrent bad breath. 

Bad breath during social interactions is such a faux pas and can be so embarrassing. Quitting a nail-biting habit can help.

Cavities

Bacteria carried in by your nails can also cause other oral health problems like cavities. Cavities are caused by bacteria that eat away at tooth enamel. 

(Did you grow up hearing that cavities are caused by sugar? That’s half true – sugar and simple carbs feed the bacteria that erodes tooth enamel, so they reproduce more and you get more cavity-causing bacteria.)

Cavities and other forms of tooth decay can have serious consequences for your pearly whites. The habit of nail-biting can cause cavities in people of all ages, leading to long-term dental problems and requiring expensive dental work.

Gum disease and gingivitis

Those same germs introduce during the “harmless habit” of nail biting can cause gum disease. 

Gum disease may not feel like the most important threat of nail biting, but you should take it seriously. In addition to the possible tooth loss down the road, the risk of gum disease is also correlated with a higher risk of Alzheimer’s and dementia. When you’re looking to quit biting your nails, you’re not just getting healthier and growing your nails out! You’re investing in your long-term cognitive health, healthy aging, and overall health.

Tooth grinding

Nail biters have to clench their jaw tightly to break down the thin surface of their fingernails between their front teeth and lower teeth. The repetitive action of biting down so tightly increases their likelihood of grinding their teeth. A chronic teeth-grinding habit, or bruxism, can lead to rapid tooth decay or tooth wear, tooth sensitivity, and disappearing tooth enamel. It puts significant additional stress on the chewing surfaces of your teeth. 

In addition to grinding, nail biting can lead to other structural tooth damage like chipping!

Jaw pain/TMJ

In severe cases, that teeth grinding can lead to jaw pain. Your temporomandibular joint is the two joints that attach your jaw bone to your skull. For nail biters, that jaw joint is working overtime as the biter gnaws away at their fingernails. 

Over time, this leads to jaw issues, up to and including TMJ disorders. Nail biters may find themselves with one of these disorders, which can lead to enormous jaw tension and headaches. 

If you don’t think chronic headaches are compelling reasons to quit biting your nails…then you’ve never had chronic headaches! 

Teeth shifting 

If you had braces as a child or teenager, you’ll be especially sensitive to this reason: regular nail-biting can make your teeth shift out of their proper position, creating gaps and crowding. 

In addition to the possible tooth damage, the force of biting down on your nails can shift the teeth. Once the teeth have shifted, orthodontic treatment may be required to put them back into their intended place. (Some people say that braces help them stop biting their nails — others find that the compulsion to bite is still their and end up breaking their braces!) This biting even weakens the roots of the teeth, making it more likely that they’ll shift or fall out in the future. Whether you had braces in the past or not, no one wants to end up with crooked teeth.

Overall health

Beyond that…nail-biting introduces so many germs that you run the risk of infection with all kinds of viruses and bacteria. You’ll have an increased risk of getting sick if you bite your nails, no matter how good your immune system is. Your fingers are the most germ-concentrated areas of your body!

How to quit biting your nails

The good news is, if you can quit biting your nails, that will be the end of the dental wear, chips and breaks, and the risk factors to your future health. You can’t go back and change the enamel wear that’s already happened, but you can protect your teeth going forward! It’s a difficult habit to break, but it’s possible and it’s worth it!

Here are some strategies you can try to quit nail biting.

Replacement behaviors: 

• If you mostly bite your nails as a way of fidgeting, you can try to replace that with some other object you can play with:
• carrying a stress ball can give you the muscle engagement that nail biters get from clenching their jaw shut
• ​wearing a rubber band or hair tie around your wrist can give you something to do with your hands when you are feeling anxious or fidgety
• a fidget spinner can simply keep your hands busy. Before you go out and buy one of these, ask the elementary schoolers you know if they have an old one.

Deterrents that make nail biting less appealing:

• Bitter-tasting nail polish. This specialty product is inexpensive but effective. It’s a clear nail polish with an extreme bitter taste that most people will find unpleasant enough that they won’t bite. (We used this one with both my kids to make them stop sucking their thumbs and it worked in less than 24 hours!) This will help most people but apparently some people like or adapt to the taste. These nail polishes are inexpensive and can be helpful!
• Manicures. With or without nail polish, a regular grooming practice and the habit of getting your nails professional cleaned, cut, and buffed may be an effective deterrent to some. 
• Gel, dip, or acrylic nail extensions. All of these are different types of additives that can be placed on your natural nails to make them thicker and stronger. If you are open to the idea of a salon manicure (or its DIY counterpart!), it’s a strategy that will strengthen and thicken your nails, making it much harder to bite through them. The look of “done” or manicured nails is not for everyone, but if you’re open to it, it’s an easy way to deter nail-biting and protect the health of your teeth.
• Keeping your nails extremely short. For some, daily nail-clipping can ensure that there’s just nothing to bite. Though doing this daily may be a chore, this may help some habitual nail biters to quit, especially if you combine it with one of the replacement behaviors above. 
• Focusing on the germs. If you are a hygiene-oriented person, focusing on the germs on and under your nails may help you feel the disgust that can help you resist biting. I read a description of this online, where a journalist described quitting in this way. This won’t work for everyone, but you can try imagining the grossest bacteria you can — e. coli or c. diff — and imagining that that’s what’s under your nails. 

​Quitting nail-biting is certainly worth it, and it’ll help protect the health of your nails, your teeth, your mind and your body. Focusing on the short- and long-term severe consequences of nail biting can help you stay motivated to quit, and experimenting with replacement behaviors and deterrents can help you find a combination that will work for you. This common habit can lead to serious problems, but you can reduce your risk of issues by quitting ASAP. 

Have you made a plan to quit biting? Tell me in the comments! 

If you liked this post, you may also like:

• How to Remove the Sticky Residue From Gel Nails FAST (2024)
• Best Body Skincare Routine for Dry Skin and Keratosis Pilaris