From tree resin and paraffin wax to Juicy Fruit, people have chewed gum (or gum-like substances) for thousands of years. So it makes sense there’s more to the habit that fresh breath or a little masticatory diversion. A lot more, it turns out.
Chewing gum can boost your mood and alertness while combatting stress. That’s according to several recent studies, including one 2009 effort from Australian and UK researchers. “There is evidence that chewing increases blood flow to the brain, and this may contribute to the increase in alertness that is consistently associated with gum chewing,” says Dr. Andrew Scholey, co-author of that 2009 paper and director of the Centre for Human Psychopharmacology at Australia’s Swinburne University.
In terms of gum’s mood-elevating anti-stress powers, Scholey says chewing the stuff seems to reduce your levels of the stress hormone cortisol. Another study, this one from a team at Eastern Illinois University, found gum helped high school students relax while taking the ACT. But exactly how gum pulls all of this off is still a bit of a mystery.
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One possibility: Research shows your stress tends to spike when you’re feeling peckish. (It’s one of the reasons some people get “hangry” between meals, experts say.) Chewing gum may temporarily turn off some of your brain’s stress-elevating “I need food” alarms, and so it may help lower worry and improve calm.
But when it comes to gum and your diet, things get tricky. While some people swear gum helps them cut back on snacks and at mealtimes, chewing certain flavors of gum at the wrong time may be problematic for people hoping to eat healthier.
According to a study from the University at Buffalo, those who chomped on mint gum before eating were less inclined to reach for healthy stuff like fruit, though their enthusiasm for junky foods like potato chips was undiminished. That study’s author, Dr. Jennifer Temple, jokingly refers to this as the “brushing your teeth before eating fruit” effect. She explains, “For some people, mint makes fruit taste awful.”
Temple’s experiments also showed people who chewed gum frequently ate fewer meals than non-chewers—but tended to load up on calories when they did eat. While many interpreted this as proof that gum isn’t an effective diet aid, Temple says her experiments only included mint gum, and put some burdensome restrictions on the gum chewers’ eating behaviors, such as forcing them to chew a piece 15 minutes before every meal.
Another study, this one from the University of Rhode Island, had people chew gum throughout the morning hours. Those people ended up swallowing 67% fewer calories at lunchtime, compared to their midday meals on a day when they didn’t chew gum. And no, they didn’t make up those calories during the afternoon and evening.
“I would say avoid mint gum just before meal times, because we found it encourages lower consumption of fruits and vegetables,” Temple says. “But in terms of replacing snacks with gum, that could be beneficial.” She adds, “There are still lots of open questions our research didn’t answer.”
So while the specifics of gum-as-diet-aid are still murky, one piece of advice is clear: If you’re going to chew, choose sugar-free gum. While sugar-sweetened gum is bad for your teeth, the American Dental Association says chewing sugarless gum stimulates saliva flow, which reduces plaque and helps prevent cavities. A 2012 review of nearly 600 research papers came to the same conclusion; chewing gum is good for your teeth, so long as you’re chomping on the sugar-free stuff.
Gum may provide a quick pick-me-up if you’re feeling frazzled, unfocused or famished. And while chewing the mint varieties before meals or snacks may lead you to select less-healthy foods, a stick of sugar-free gum after a meal could protect your teeth from cavities.