For decades now, endurance athletes and their dentists have wondered whether sipping sugar-filled sports drinks is putting their teeth at risk. You’ve got a sweet, acidic drink that you’re encouraged to sip frequently for hours at a time, while exercising hard enough to reduce the flow of saliva that would otherwise protect your teeth. That’s bad news.
Still, despite the scary stories that circulate now and then, there’s not a whole lot of evidence to tell us how bad this problem really is. Dental exams in the Olympic Village in 2012 found that 55 percent of athletes had cavities—which sounds bad until you consider that the overall prevalence of cavities among American adults is 92 percent. A small 2015 study found that cavity risk was proportional to training hours in triathletes. On the other hand, Gatorade’s parent company funded a 2002 study that found no association between sports-drink consumption and dental erosion, which probably doesn’t reassure you.
In other words, this is a question crying out for more and better data. A new study in the Scandinavian Journal of Medicine and Science in Sports, from a group led by Cordula Leonie Merle and Lisa Richter of the University of Leipzig, makes a modest start. They compared 88 elite endurance athletes, mostly runners and biathletes, all competing for German national or developmental teams, with 57 non-competitive amateur athletes. Crucially, unlike some of the previous studies in this area, they didn’t just ask them about their health: all subjects received a detailed dental check-up, including assessments of tooth decay, plaque, and gum health, from the same dentist.
The good news: both groups had low levels of plaque, gum inflammation, and tooth erosion. Both groups also had similar numbers of decayed, missing, or filled teeth: 2.7 for the athletes, 2.3 for the controls. But if you narrow that down to just decayed teeth, there was a significant difference: 0.6 for the athletes, with a prevalence of 34 percent; 0.3 for the controls with a prevalence of 19 percent.
There were a few other differences. The athletes also tended to have deeper pockets between the teeth and gums, which is a warning sign of periodontal disease. And they were more likely (43 percent versus 25 percent) to exhibit temporomandibular dysfunction, which indicates problems with the jaw muscles or joints such as clicking when you chew.
It’s hard to blame jaw clicking on sports drinks, which is an important point. Maybe competitive athletes are so wound up that they spend a lot of time clenching their jaw or grinding their teeth at night—or maybe there are some underlying differences between the two groups that have nothing to do with what they drink. For example, socioeconomic status is one of the key predictors of dental health (people with high incomes have more cavities overall, people with low incomes have more untreated cavities).
The Leipzig study did assess oral hygiene habits such as tooth-brushing and dental checkups, which were similar between the two groups. They didn’t assess specific behaviors like sports-drink use. Overall, I don’t think the results make a convincing case that endurance athletes are at heightened risk of tooth problems, but they don’t rule it out either.
What can you do to protect yourself from this potential risk? One common piece of advice is to rinse your mouth out with water after drinking sports drinks, to both clean the teeth and promote saliva flow. The makers of Maurten, the hydrogel-encapsulated sports drink, have published data suggesting their drink produces a less acidic biofilm on your teeth compared to other sports drinks.
But probably the most encouraging results I saw came from a four-year randomized trial of 54 endurance athletes, mostly triathletes, half of whom tested a fancy new toothpaste and mouth rinse containing stannous fluoride, a novel fluoride compound that has antimicrobial properties in addition to the cavity-fighting and enamel-strengthening properties of regular fluoride compounds. The study was funded by the German subsidiary of Colgate.
The results of the trial were exceptionally encouraging. After four years, the chances of a given tooth surface showing signs of decay during the biannual checkup had dropped by a factor of 25! This is a stunning transformation. The key twist: there was no difference between the experimental group and control group: the fancy toothpaste didn’t matter. The mere fact of being enrolled in a study that forced them to focus on their dental hygiene habits, along with visits to a dentist every six months, radically altered the subjects’ oral health. So that’s the radical advice I’ll leave you with: brush your teeth, see your dentist for regular checkups, and keep training.
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