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Gum is something to chew on, especially when taking a test

Back in 2002, researchers at the University of Northumbria in England assigned 75 subjects age 24 to 26 to either chew gum, mimic chewing without gum or not chew at all while performing both short- and long-term memory tests. Gum-chewers scored significantly higher.

I will tell you up front that I don’t like chewing gum. I know studies have shown that chewing may reduce tooth decay, help with weight management and even reduce stress, but I’m not won over. And it isn’t because I’m worried about the “carcinogens, petroleum derivatives, embalming fluid ingredients or chemicals that cause diarrhea or mess with our digestive system” — the kind of accusation that permeates the Internet, authored by scientific luminaries with self-conferred titles such as “Food Babe.”

My aversion to gum probably traces back to elementary school, when one of my teachers had a unique punishment for anyone caught chewing gum in class. The criminal had to climb on a chair and recite: “The gum-chewing student and the cud-chewing cow differ somehow. I know, it must be the intelligent look on the face of the cow!” Ever since witnessing such a “sentence” being carried out, I can’t look at a masticator without comparison to a cow, decidedly to the animal’s advantage. Memory sure is a mysterious thing. And therein lies a gummy story to chew on.

Back in 2002, researchers at the University of Northumbria in England assigned 75 subjects age 24 to 26 to either chew gum, mimic chewing without gum or not chew at all while performing both short- and long-term memory tests. Gum-chewers scored significantly higher. Although the robustness of this study has been criticized, it did unleash speculation about why chewing gum may aid memory. For one, research has shown that chewing gum increases blood flow to the brain and activates the frontal and temporal cortex, probably by enhanced oxygen transport. Since these regions are known to play a role in cognitive function, increased memory seems a possibility. Another option is “context-dependent memory,” implying that information is more easily recalled in an environment similar to the one experienced while learning, particularly if a smell is involved. For example, students studying while exposed to the scent of chocolate perform better when exposed to the same scent while writing exams.

In 2011, Matthew Davidson of Stanford University’s School of Medicine explored the memory-enhancement effect further, adding another twist. He fortified the gum with substances that have been associated with improved cognition. Many studies have suggested improved alertness with caffeine, so it was a natural additive. (In fact, the U.S. army has introduced caffeinated gum in military rations.) Davidson also added an extract of the ginkgo biloba tree and vinpocetine, derived from the lesser periwinkle; both have been shown to enhance blood flow to the brain. Also included was an extract of a creeping herb known as Bacopa monniera, which in at least one placebo-controlled, double-blind study was shown to improve learning rate and memory. Rosemary and peppermint were also added, mostly to take advantage of their strong scent, which may enhance recall. The 62 participants were divided into three groups; they chewed either the “Think Gum,” ordinary bubble gum or nothing while engaged in learning as well as during recall.

The results were not exactly spectacular, but the herbal/caffeinated gum-chewers did perform better on most tests, in some cases by as much as 30 per cent, than did the non-chewers. Bubble-gum chewers did only marginally better than non-chewers, suggesting that the effects noted were cathe gum’s additives rather than to chewing. While “Think Gum” may be a helpful study aid, the product’s advertising slogan of “stop cheating, start chewing” is a bit hard to swallow.

What is even harder to swallow is the diatribe directed at chewing gum on some websites and circulating emails. Here is one gem: “Gum is typically the most toxic product in supermarkets and is likely to kill any pet that eats it … loaded with harmful ingredients and chemicals.” (Hmm, I wonder what sort of ingredients don’t contain chemicals?) One of the “harmful ingredients” highlighted is butylated hydroxyl toluene, a preservative. The basis of the scare? BHT is found in embalming fluid. Yes it is, but so what? BHT is an approved food additive that prevents fatty substances from reacting with oxygen. It is sold in pill form in health-food stores as a dietary antioxidant.

Another “toxin” we’re supposed to worry about is vinyl acetate. This is indeed a worrisome substance if exposure is significant, but that isn’t the case with gum. These days “gum base” is mostly made of synthetic rubber rather than natural substances like the sap of the sapodilla tree, commonly known as “chicle.” The synthetics include styrene-butadiene rubber, polyethylene and polyvinyl acetate. In theory, PVA may contain traces of vinyl acetate, the chemical from which it is made, but the amount is trivial. Science lies in the details.

The scares about gum that go around today, however, can take a back seat to the one that rocked the Egyptian city Mansoura in 1996, when loudspeakers blared out warnings to girls about the evils of chewing gum “laced with aphrodisiacs capable of transporting the most innocent female into a sexual frenzy.” Sold under the brand names Aroma and Splay, the gum was said to be an Israeli attempt to corrupt Egyptian youth. Laboratory analysis by Egypt’s ministry of health found nothing other than the usual ingredients, but that didn’t stop authorities in Mansoura from closing any kiosk that dared sell the gum that supposedly caused young women to engage in immodest activities.

Speaking of immodest activities: how about a gum that claims to increase bust size? Bust-Up gum contains miroestrol and deoxymiroestrol, two estrogen mimics found in the underground tubers of a plant called Pueraria mirifica. Lack of evidence for the reputed benefit notwithstanding, it is curious that some women who may be concerned about trace amounts of estrogen mimics leaching out of plastics will swallow significant amounts of phytoestrogens when it comes to trying to improve their appearance.

And now for a final bit of nonsense. Calcium casein peptone-calcium phosphate is an ingredient in Trident gum. Various alarmists warn about it with inspired comments like “casein is a milk-extractive that was linked with the Chinese baby formula poisonings.” Casein is indeed a protein found in milk, but it has nothing to do with the poisonings, which were caused by formula being adulterated with melamine in an attempt to increase protein content. CCP actually remineralizes tooth enamel by delivering calcium and phosphate beneath the tooth’s surface. The scare about it is just another example of the rampantly galloping chemophobia we’re witnessing. That stresses me. Maybe I should chew gum.




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