We all know that eating sugar is bad for our teeth, but have you ever wondered just how bad? Hopefully, you practice good oral hygiene, brushing and flossing regularly, and have never seen the harmful effects. If you’re particularly on top of things, maybe you even use an electric toothbrush or a water flosser. There are review websites out there to help you find the best water flosser for different needs, including braces, or even some designed specifically for gum disease. In between cleanings, though, your mouth is a hotbed of microscopic activity, and if you care about your teeth, you’re probably curious what role sugar plays in all this. So: what exactly is going on in your mouth when you’ve spent all day munching on sweet stuff and washing it down with sugary drinks?
It might surprise you to learn that sugar itself isn’t inherently harmful. The consumption of sugar isn’t what does damage to your teeth; the role of sugar in tooth decay comes along a bit later in the process. The most important thing to know is that our mouths are filled with bacteria. Anywhere from 500 to 1,000 different types are a part of the oral microbiology, with approximately 100 to 200 living in the mouth at any given time. Some of these are beneficial to the oral ecosystem, working alongside the immune system to fight dangerous germs and keeping fungus growth in check, but a good number of strains are less benevolent. When they grow, they form a sticky layer of film, what we all know as plaque.
This is where sugar gets involved. The sugar you eat doesn’t go toward feeding just you, it’s also a prime source of energy for the bacteria living in your mouth. These bacteria take in sugar and churn out acids, which is where the problematic interactions arise. The acids produced leech minerals from the enamel of the teeth, the shiny, protective layer that coats each tooth.
This demineralization process doesn’t spell certain doom for your teeth; in fact, it operates more like a game of tug-of-war. Plaque damages the enamel, then natural enzymes in saliva and chemicals like fluoride remineralize your teeth in a back and forth conflict that rages on all day, every day. Saliva contains mineral salts like calcium and phosphates that help to reharden enamel, a job fluoride also performs. This helps stop the acids from eating through the enamel, leaving the tooth more porous, eventually creating a hole large enough to be qualified as a cavity. Cavities rapidly fill with bacteria, creating a vicious cycle wherein the tooth decays more and more as the hole enlarges, allowing more bacteria in that produce more acid that further enlarges the hole.
While this might sound like common sense— we’ve all more than likely been lectured by our dentists before— the correlation between sugar and tooth decay is extremely profound. Researchers have gone so far as to say it’s the only thing that causes tooth decay in humans. One study found that the percentage of Nigerians who had experienced tooth decay was as low as 2 percent, where diets typically include little to no sugar: under 2 grams a day. In stark contrast, the United States reports approximately 92 percent of adults have experienced some sort of tooth decay. This is particularly horrendous as scientists uncover links between oral health and more and more ailments, particularly cardiovascular disease and diabetes.
What about the natural sugars found in fruit and 100% natural fruit juices? Somehow it doesn’t seem right to advise someone to stop eating fruit or fruit juices if they want to save their teeth from tooth decay. But the fact is fruit contains sugar, and sugar is sugar. Natural fruit juice can contain as much sugar as soda. Just remember to clean your teeth after eating something sugary, as fruit is an important part of our diet.
In light of the link between oral health and ailments, the World Health Organization has recommended adults consume only 5 percent of their daily calories in the form of sugar. All sugars are not consumed equally in this regard: sugars consumed during meals, rather than between meals, have less of an effect. Swapping to or taking up chewing sugarless gum can also help, as saliva plays a protective role in oral health and chewing gum increases saliva production. Most of all, be sure to brush and floss regularly, and you’ll keep those teeth gleaming.