A new study suggests that mouthwash may cause diabetes? When I first saw the study, my first thought was how much mouthwash? My second thought was that I probably owe some apologies to a few classmates from my elementary school days. Let me explain.
Back in the late 80s, if you sat in the back of a school bus in Chicago or its South Suburbs, there was one skill you had to master…the art of the hilarious, yet not overtly offensive insult. Walking to the back of the bus was like stepping into an alternate dimension where parental influences were non-existent. Curse words, black-market lunch trading, and soul-damning insults from preacher’s kids were all fair game. It was like the front of the bus was ‘Wakanda,’ and the back of the bus was The Wire.
I was a small kid with glasses and good grades who took up residence in the back of the bus. Becoming a masterful tactician at roasting was necessary for my survival (I only used roasting as a defense mechanism. I was never a bully, nor do I encourage bullying). My inspirations for roasts typically came from movies. One movie was Kid n’ Play’s, House Party.
In the movie, people repeatedly referred to Martin Lawrence’s character as having ‘Dragon Breath.’ As an adolescent, I thought the concept of comparing someone’s breath to dragon fire was groundbreaking. It was metaphoric genius in my eyes. From that moment on, any breath in the back of the bus, aside from my own, was ‘dragon breath.’ Anytime anyone would hurl an insult at me, I served them with a non-sympathetic reflex response that included some variation of ‘Dragon Breath.’ Classic lines like, “What’s Billy’s (not a real person) favorite karate movie? Enter the Dragon Breath,” inspired a cadre of precocious pre-teens to invest in bottles of Listerine and Scope.
Thus, the possibility that excessively using mouthwash can raise the risk of diabetes means I may have to dish out some apologies.
Does using too much mouthwash promote diabetes?
The study evaluated 1206 people with excess weight as a risk factor for diabetes, aged 40-65 years old. The participants filled out questionnaires assessing smoking, physical activity, alcohol consumption, income, education, and oral hygiene. The researchers also followed the participants for 3 years and measured blood glucose (sugar) levels throughout the study period.
The study revealed that “participants who used mouthwash twice daily [or more] had 55% significantly increased risk of developing pre-diabetes or diabetes over a 3-year follow-up compared to less frequent users, and 49% higher risk compared to non-users of mouthwash.”
Why would mouthwash have any effect on diabetes?
At face value, mouthwash shouldn’t have any effect on developing diabetes. It’s not like Listerine can pass for a sanitized version of Coca-Cola. Furthermore, we’re not even supposed to swallow mouthwash. Having fresh breath is a sign of good health, right?
Well, like many things in life (especially relationships, politics, and the inexplicable popularity of trap music), it’s complicated. Apparently, the bacteria that reside in the mouth play a significant role in our overall health. My father and brother, both dentists, are probably doing a ‘touchdown’ dance somewhere as they’re reading this.
The concept that oral health has implications beyond toothaches is not new. Multiple studies have identified links between periodontal (gum) disease and heart disease. As a gastroenterologist, the importance of the mouth’s bacteria (or bacteria in general) also isn’t surprising. You can’t step foot in any conference for gastroenterologists without hearing at least 31 reasons why the gut’s bacteria are on par with midi-chlorians from Star Wars.
The mouth contains at least 700 different types of bacteria. These bacteria aren’t just loitering on your tongue—they are physiologically active. One important activity associated with a few of the bacteria is converting nitrates contained in food into Nitric Oxide. Nitric Oxide plays roles in relaxing blood vessels and decreasing insulin resistance.
Several studies suggest that the anti-bacterial properties associated with mouthwash can kill off significant populations of the mouth’s bacteria and subsequently decrease the levels of nitric oxide in the body. Depleting the mouth’s bacteria may dampen the health benefits associated with consuming nitrate-rich vegetables such as spinach and beets (check out my beet article).
Thus, just like overusing antibiotics, you may want to think twice before using mouthwash several times per day.
Isn’t mouthwash good for oral health?
Although I don’t use the term ‘Dragon Breath’ anymore, no one wants to have halitosis or bad breath. It’s worth noting that halitosis isn’t even a medical term—its origins lie in a marketing campaign created by the owners of Listerine.
What’s the Bottom Line?
- Brush your teeth
- Try not to use mouthwash more than 1-2 times daily (unless your dentist/orthodontist/doctor tells you otherwise)
- Don’t tell people they have ‘Dragon Breath.’ That was cool in 1990—you may need to consider the possibility that you’re a jerk if you’re an adult using that phrase in 2018 #ijs.
I am a physician and trained chef. I specialize in gastroenterology and nutrition. Currently I work as the Associate Director of Adult Nutrition at the University of Chicago.