You wouldn’t dream of leaving the house in the morning or going to bed at night without brushing your teeth (at least I hope you wouldn’t!). And ideally, you give your pearly whites a good daily flossing, too. But if you’re also accustomed to swishing some mouthwash—to sweeten your breath, whiten your teeth, fight infection or make your mouth “feel really clean”—I urge you to take two specific precautions.

Another alert: If you’re a denture wearer, you also need to be on guard. Here’s why…


For a recent study, researchers from nine European countries interviewed nearly 2,000 men and women who had been recently diagnosed with oral cancer—malignancies of the mouth, larynx (voice box), pharynx (throat) or esophagus. For comparison’s sake, they also interviewed a similar number of age-matched but cancer-free people who served as controls.

All of the participants were asked about various lifestyle and dietary habits…their oral hygiene habits…and their medical and dental history. When the researchers analyzed this data (and adjusted for smoking and alcohol consumption, two known risk factors for oral cancers), they came to some predictable conclusions—for instance, that failing to brush teeth twice daily or to visit the dentist at least annually was associated with significantly increased risk for oral cancer. But they also found two surprising risk factors

  • Wearing dentures. Even partial dentures were associated with increased risk. And people who wore complete upper and lower dentures had nearly double the risk of people who did not wear dentures. Oral cancer risk was especially high among those who started wearing dentures before they were 55 years old.
  • Frequent use of mouthwash. Compared with people who did not use mouthwash, those who rinsed their mouths with mouthwash three or more times each day had about triple the risk for oral cancer. However, there was no increased risk found among people who used mouthwash less frequently than three times a day. Noteworthy: Unfortunately, this study did not distinguish between mouthwash that contained alcohol and mouthwash without alcohol. Some previous, smaller studies suggested that both alcohol-containing and alcohol-free mouthwash may increase oral cancer risk, but other studies found increased risk only with mouthwashes that contain alcohol…and as pointed out previously, alcohol is a known carcinogen.

Double jeopardy: For people who both wore dentures and used mouthwash three or more times daily, the risk for oral cancer was multiplied more than seven times!

For optimal oral health…

  • Clean your teeth well every day…and to make sure you’re doing it right, check out Don’t Make These Common Mistakes When Brushing and Flossing.
  • Visit your dentist two or more times each year. If the very idea makes you cringe, read Afraid of the Dentist? Don’t Be—The New Dental Visit Is Pain Free.
  • If you are a fan of mouthwash, there’s probably no need to stop using it altogether—but it may be wise to stick with brands that are alcohol-free and  limit your swishing to no more than once or twice a day.
  • What if you have dentures? You can’t change that—but you can be extra vigilant about watching for possible signs of oral cancer, such as a slightly raised white or red patch in the mouth…an unexplained lump in the neck…discomfort on one side of the throat…subtle changes in voice…unexplained and persistent ear pain…or difficulty or mild pain with swallowing. Remember, as with many diseases, the earlier oral cancer is caught and treated, the better the outcome generally is.