Can Running Ruin Your Teeth?

Posted by Filed Under: Health & Fitness, Running Tips

Recently, I had a disappointing visit to my dentist. “Why so glum” you ask? Well, he found three cavities (tiny ones but still).

Honestly, I’ve never had the toughest chompers—even as a kid I struggled with cavities whereas, my brother could chew on stones, never brush his teeth, and still never get a single cavity. But, I digress.

Because of my dental vulnerability, I am pretty diligent with my teeth so when this latest disappointment happened, I was really unhappy and I think it showed.

My hygienist (Daniella) came in and promptly began chatting me up about the problem. “Do you brush?” (yup). “How often?” (usually three times a day) “How about flossing?” (ok, you got me there).

Even with my spotty flossing, Daniella said I shouldn’t be having the trouble I’m having. She paused. And then a light bulb went on over her head (maybe it was the dentist’s lamp?) and we had the following conversation.

Daniella: “Are you running a lot?” (she knows I am a runner)
Me: “Yes, I’m running a lot. Way more miles than ever, actually”
Daniella: “Hmmm …and do you breathe through your mouth, or your nose?”
Me: “I’ve tried to breathe through my nose but I can’t most of the time so, I guess that means I breathe through my mouth.”
Daniella: “And do you drink a lot of sports drinks like Gatorade?”
Me: “Not really. I used to but I mostly stick with water now.”

Then Daniella explained to me that many of the “hardcore” runners she knows (I love that she called me that) have the same problems I have with their teeth. She said that sports drinks are really hard on teeth—especially when you drink them before or during your runs so she was happy I wasn’t drinking those (here’s a related article that claims sports drinks are harder than Coke on your teeth).

But, even without the sports drinks, I was experiencing worse-than-average tooth decay. The culprit? Breathing through my mouth. Daniella explained that when you run great distances with your mouth open, it can dry your teeth out and, without the protection we get from saliva, any bacteria we have in our mouths can get to work on destroying our teeth.

As I struggled with the irony that my healthy habit was contributing to unhealthy teeth, Daniella laid out a plan of attack for me:

  1. Brush teeth before running (this part didn’t surprise me!).
  2. Swish/gargle with “weekly strength” (not daily strength) mouthwash. I was told that the weekly product has 0.2% of the active ingredient compared to 0.05% in the daily version. In other words, it is stronger and protects better.
  3. Run.
  4. After running, swish with mouthwash again.

The strategy behind this plan is to:

  1. Remove as much decay causing bacteria as possible before running,
  2. Coat the teeth with a protectant, and
  3. Follow up with more brushing and swishing as soon as you can after running.

I am hoping that following this regime will make my next visit to the dentist a more positive one.

How about you? Have you experienced this problem?

About Mark Iocchelli

Also known as the "Running Blogfather", I'm a 40-something marathoner who has beaten stress fractures and terrible shin splints. Now I'm running double the mileage with no pain - and I'm getting faster. I love to talk about running form and Arthur Lydiard. I also enjoy taking photographs, have a beautiful (and very patient!) wife, and am the proud father of two crazy kids. Feel free to contact me if you have any questions or comments about the site.

  1. thodarumm on April 26th at 7:05 am

    Who would have thought?
    This is too eerie, its like you read my e-mail. I wrote about teeny tiny cavities that my dentist finds whenever I visit him and I have your dental hygeine habits.. brush well, floss..huh.
    My hygeinist gives me different kinds of floss ‘thingis’ to encourage me to do it, but I just never grew up with that concept in India and won’t do it. The most I do is to poke around with Stimudent. Anyways, I asked my friend if dentists just fill ‘imaginary’ cavities.. I am becoming suspicious with mine.

  2. Blaine Moore (Run to Win) on April 26th at 7:29 am

    I haven’t heard of this specific problem, but I remember when I was younger that I read that brushing your teeth before a long bicycle ride was good for you.

    I believe that the reasoning was that you don’t salivate as much after brushing and would take longer to get dehydrated, but this was 15 years ago that I read that tip and I never paid much mind to it.

  3. Jeanne on April 26th at 10:00 am

    no wonder i’ve had 3 root canals, one tooth pulled and a crown since january! you’d think i’d been logging 80 miles/week!

  4. Soozan on April 26th at 1:16 pm

    That must explain my “no-cavity” dentist visit today.

  5. Soozan on April 26th at 1:16 pm

    oh, and the new forum is really cool.

  6. William F. Vann, Jr. on April 26th at 5:37 pm

    I’m an academic dentist and have been running long distances for nealry 30 years. I’m also familiar with the published literature examining the realtionship between sports drinks and dental erosin; the studies are weak and I don’t buy it!

    The business related to breathing is a new twist but I don’t understand the theoretical rationale. I don’t buy that either. The advice to brush before running? Brushing is always good but I don’t buy it!

    Im concerned that you dentist or hygienist didn’t recommend a fluoride mouth rinse. Unless you’re running with your mouth constantly full of gu or hard candy (as does one of my running with a mouth full of crowns–no wonder!), I don’t think running had anything to do with your dental condition. bill

  7. Mark Iocchelli on April 26th at 5:46 pm

    Hi Bill! Thanks for chiming in with expert advice! My hygenist *DID* recommend a floride mouth rinse. I guess my article was not clear in that regard? I will make a clarification shortly.

  8. Ron on April 26th at 7:10 pm

    I don’t buy it either. After the countless nights sleeping with my mouth open, I should have lost at least one tooth by now. Oh yea, I run with it open too.

  9. Jon (was) in Michigan on April 26th at 8:45 pm

    I’m no dentist but I agree something is amiss.

    Cavities from mouth breathing? That just doesn’t sound right. Mouth breathing may give you receding gums but not cavities from lack of saliva. That’s just crazy.

    A colleague at work had a dentist that constantly found “tiny” cavities in all her teeth. When she was moving to a new job, she went for a final check up and he said her xrays looked clear. Then she said she was moving out of town. Suddenly he wanted to “recheck” the xrays and lo and behold! He found four! She ditched him instantly. When she got here, she found a new dentist who checked and said she had ZERO cavities.

    My son went to a special kid dentist here when we arrived in from Michigan, and was told he had two cavities that needed filling immediately. He had never had a cavity before and the kid uses floss and dental rinse every day and sees the dentist every 6 months. We went to another dentist and he told us there was NOTHING there at all. Even when we showed him exactly where the “cavities” were supposed to be.

    I’m not saying your dentist is dishonest, but something about what she is saying just isn’t making sense.

  10. thodarumm on April 27th at 7:42 am

    Aha.. Thanks Jon from Michigan. The plot is getting thicker. I am not fillin the recent tiny cavity that my dentist has discovered.. I really don’t think I have one.

  11. Afty on April 27th at 9:48 am

    My dentist is a serious runner with several Bostons under his belt, and he’s never mentioned anything to me about running being bad for the teeth.

  12. Melanie on August 13th at 2:03 pm

    I’ve had an ongoing issue with mouth dryness, causing receding gums, since I began running 8 months ago. One word: Biotene. It has helped me with this. I use a waterpik inbetween brushings, followed with Biotene to alleviate dry mouth. Results: Not such swollen gums.

  13. Jim Wilson on July 17th at 3:02 pm

    There’s a new product on the market specially formulated for Dry Mouth–Salese (formerly Saleve). It’s a long-lasting soft lozenge that you place in your mouth (do not bite or chew) and it slowly dissolves in your mouth over an hour or longer. It keeps your mouth moist and it has anti-bacterial ingredients to kill bacteria that cause cavities and bad breath. Go to for more info and to order. You can run all you want while keeping your mouth moist and improving your oral hygiene.