Friday Favorites: How to Stop Tooth Decay

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Dental cavities may be humanity’s most prevalent disease, affecting 35 percent of the global population. The average number of decayed, missing, and filled teeth has been estimated at more than two—by age 12. In the United States, the oral health of our elderly may also be in “a state of decay,” with one-fourth of elderly persons missing “all their teeth.” And an estimated hundred billion dollars of all that is due to sugar.

Sugar consumption is considered the one and only cause of cavities. Though often referred to as “a multifactorial condition,” the other factors—the bacteria, the plaque, the saliva, the brushing, the flossing—appear to just have mitigating influences. “[A]ll the other factors simply modify the speed” by which sugar causes cavities. “Without sugars, the chain of causation is broken, so the disease does not occur.” We might not even need all that stuff if we could just get rid of added sugar.

Studies dating back “decades ago showed that in countries where sugar consumption was very low, dental [cavities were] almost non-existent.” And: “New analyses show that the life-long burden of [cavities] increases as sugar intakes increase from [zero].” “The most comprehensive national data are from…Japan…before, during, and after World War II,” where the incidence of cavities tracked per capita sugar intake as it dropped from about 8 percent of calories down to just 0.1 percent—less than a teaspoon a week—before rebounding to about 14 percent. Such studies show that cavities continued to occur even when sugar intake comprised only 2–3 percent of caloric intake. Given that more extensive disease in adults doesn’t appear to manifest if sugar intakes are limited to less than 3 percent of caloric intake, a public health goal to limit sugar intake to below 3 percent has been recommended. This led to the suggestion that traffic light food labels mark anything above 2.5 percent added sugars as “high.” That would make even comparatively low-sugar breakfast cereals, such as Cheerios, “red light” foods.

The recommended 3 percent cap on total daily intake of added sugars wouldn’t even allow for a single average serving for young children of any of the top 10 breakfast cereals most heavily advertised to them. Obviously, soda is off the table. One can has nearly two days’ worth.

The American Academy of Pediatric Dentistry adopted the more pragmatic goal, recommending sugar intake stay below 5 percent for children and adolescents, matching to the World Health Organization’s conditional recommendations for both children and adults. That’s about where sugar dropped to in Iraq when they were under sanctions, and it cut cavity rates in half within just a few years. Of course, the sanctions may have cut other things, like children’s lives, short— though that was apparently fake news, a consequence of government manipulation.

Anyway, if we were really interested in minimizing disease, the ideal goal would be to drop the intake of free sugars to zero—meaning added sugars. They’re not talking about sugars naturally found in breast milk, or the intrinsic sugars found in fruit. But when it comes to added sugars, there does not seem to be a threshold for sugar intake below which there are no adverse effects; an exponential increase in cavity rates for sugar intakes even starting as low as 1 percent.

Yeah, maybe we could get rid of cavities “if there is no sugar in the diet,” wrote a Kellogg’s-funded researcher; “this ideal is impractical.” “[T]he dictatorial use of foods ‘friendly to the teeth”’ might promote “dietary celibacy…not…acceptable to all individuals.”

“Instead of recommending draconian reductions” in sugar intake, the sugar industry responded, “attention would be better focused on…fluoride toothpaste.”

You know, that’s the perfect metaphor for medicine’s approach to lifestyle diseases in general: why treat the cause when you can just treat the consequences? Like, why eat healthier to prevent and treat heart disease, when we have all these statins and stents?

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Image credit: Suyash.dwivedi via Wikimedia. Image has been modified.

Motion graphics by Avocado Video