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.

“Horace Fletcher,” proclaimed one of his obituaries in 1919, “taught the world to chew.” Also known as the “Great Masticator,” Fletcher was a health reformer who popularized the idea of chewing each mouthful more than 32 times (“once for every tooth”). It wasn’t put to the test, though, until nearly a century later. People were told to eat pasta until they were “comfortably full,” but were randomized to either “Chew each mouthful 10 times” or “Chew each mouthful 35 times” before swallowing. The subjects were told it was a study about “the effects of chewing on mood” — but that was just a ruse. What the researchers really wanted to know is whether “prolonged chewing reduce[d] food intake.” And, those who chewed more felt full earlier than those who chewed less, such that they ended up eating about a third of a cup less pasta overall.

If chewing in some way suppresses your appetite, what about chewing gum as a weight loss strategy? An article entitled “Benefits of Chewing Gum” suggested as much, but it was written by

“the executive director of The Wrigley Science Institute.” Let’s see what the science says.

Big Gum likes to point to this letter published in The New England Journal of Medicine back in 1999. Mayo Clinic researchers claimed gum chewing could burn 11 calories an hour. Critics pointed to the fact that they didn’t really test typical gum chewing, instead chewing the equivalent of four sticks of gum “at a very rapid cadence.” Specifically, they were “instructed to chew at a frequency of precisely 100 Hz” for 12 minutes. That seemed to burn 2.2 calories, hence potentially 11 calories an hour.

One might have had more confidence in the Mayo scientists’ conclusion had they not lacked a fundamental understanding of basic units. A hundred Hz would mean 100 chews per second—that would be a very rapid cadence indeed. If the 11 calories an hour is true, though, that might mean you could burn more calories actively chewing gum sitting in a chair than you would not-chewing-gum upright at a standing desk.

But chewing one small piece of gum at your own pace may only burn about three calories an hour, which would approximate the calorie content of sugar-free gum itself. But chewing off the calories of a piece of sugar-sweetened gum might take all day. But what about the purported appetite-suppressing effect of all that chewing?

The results from studies on the effects of gum chewing on hunger are all over the place. Some studies show decreased appetite, some showed no effect, and one even showed significantly increased hunger after gum chewing among women. The more important question, though, is: are there any changes in subsequent calorie intake? Again, the findings are mixed. One study even found that while gum chewing didn’t much impact M&M consumption, it did appear to decrease the consumption of healthy snacks. Ah, but they used mint gum, and the healthy snacks included mandarin orange slices; so, this may have just been an orange-juice-after-tooth-brushing effect.

It can take an hour before the residual taste effect of mint toothpaste dissipates. This is bad if it cuts your fruit intake, but what about harnessing this power against Pringles? An international group of researchers had people eat Pringles potato chips for 12 minutes, interrupting them every three minutes to swish with a menthol mouthwash. Compared to those in the control groups (swishing with water or nothing at all) the minty mouthwash group cut their consumption 29 percent. The researchers conclude: “if a consumer finds themselves snacking on too many [chips]…, one potential strategy could be intervening by having a peppermint tea, menthol-flavoured chewing gum, or brushing their teeth to slow down or stop snacking.”

What really matters, though, is weight loss. Even if some tweak like gum chewing can affect the consumption of a single snack, your body could just compensate by eating more later in the day. The only way to know for sure if gum chewing can be used a weight loss hack is to… put it to the test, which we’ll cover next.

Please consider volunteering to help out on the site.