Flashback Friday: The Worst Food for Tooth Decay

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Nearly a half century ago at a Senate hearing on nutrition, a Dr. Nizel from Tufts suggested that sugary breakfast cereals “should be banned in the best interest for all concerned, particularly children”—perhaps not surprisingly, since he was a professor of dental medicine.

A dozen different foods and beverages were ranked for their “cariogenic potential”—their cavity-causing potential—by implanting electrodes in the mouths of study subjects to measure the amount of acid produced in the plaque between their teeth after eating a variety of different things. And, the two breakfast cereals they tested topped the charts.

If you drink some sugar water, the pH on your teeth plunges within minutes into the acidic danger zone, and stays there for an hour, eating away at your teeth. Caramel is worse. It sticks to your teeth, so stays longer, down deeper in the acid zone. But, check out the breakfast cereals: goes down and stays down, even two hours later.

We’ve known about the cavity-causing “potential of presweetened breakfast cereals” for decades. A dozen such cereals were put to the test to measure the level of tooth-dissolving acid produced by the strain of bacteria that causes cavities. As one might expect, “the [cavity-generating] potential was found to be related directly to the sugar content of each cereal”—though Frosted Mini-Wheats was an exception. Despite having 40 percent less sugar than cereals like Froot Loops or Frosted Flakes, Frosted Mini-Wheats caused the greatest calcium demineralization—ranking second only to the now defunct “Powdered Donutz” in cavity-causing potential. A study of twenty-eight different cereals concluded that “Unquestionably, the sugar concentrations in these twenty-eight cereals are sufficiently high to qualify them as dentally dangerous.”

Wanting to be good corporate citizens, General Mills took their Super Sugar Crisp, which was 44 percent sugar, and reduced the sugar…font size. Then, caring about children’s health so much, they removed sugar altogether…from, the name….

Kellogg’s cares, too. Though Sugar Smacks is, apparently, where “space energy comes from,” it doesn’t sound as wholesome as Honey Smacks; same cereal, healthier name. They did remove sugar from Corn Pops and Frosted Flakes; I mean, well, from the front of the boxes.

And Cookie Crisp? I think the fact that it’s made by a dog food company says it all.

But, General Mills protests: a study they did in which teens were randomized to receive free cereal delivered to their homes—or not—didn’t seem to get any more cavities, proving breakfast cereal is harmless for your teeth. Anyone care to take a guess at the study’s fatal flaw? The kids in the control group were free to just have their parents buy their sugary cereals from the store, and so both the experimental and control groups may have been eating the same cereal, “with the only difference being that the experimental group received its cereal free, and the control group” had to pay for it.

What did the General Mills researchers have to say for themselves? “Dietary controls so rigid as to exclude the ingestion of cereals by children would be difficult, if not impossible.” But then, that’s not a control group!

That’s like this Kellogg’s-funded paper saying yeah, if we didn’t feed kids sugar, then we could virtually eliminate cavities, but “this ideal is impractical.” So, let’s take the middle ground and come up with, oh, Froot Loops with marshmallows. But hey, at least they’re fruit shaped, or at least “fruity shaped.”

Observational studies have also failed to link breakfast cereal consumption with cavity prevalence though, or incidence. This is presumed to be because eating it with milk helps clear food particles from the mouth. Though Frosted Mini-Wheats did lead to the same sugar retention in the saliva ten minutes after intake, with or without milk, the other cereals were cleared out faster. “[S]ugared cereals are often eaten as snacks [by kids, though] without milk.”

And, ten minutes after the ingestion of dry sugary cereals, you’re left with nearly 50 times the sugar residue in your mouth, compared to swishing the sugar down in liquid form. “[I]t is inconceivable,” concluded the researchers, “to contest the fact that frequent between-meal ingestion of [foods like high-sugar cereal] is dentally hazardous. Whether or not meal-time eating of sugared cereals induce [cavities] is not the point…because [kids snack on them] between meals, they have a marked potential for dental danger.”

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Image credits: Ajrieger via wikia, Wokandapix via pixabay, and Jason Liebig. Images have been modified.

Motion graphics by Avocado Video