Besides freshening breath, chewing sugar-free gum helps keeps gums in good shape. "Gum pulls food particles out of all the pits and grooves in your mouth to help keep bacteria from thriving," Layliev says. Also, chewing gum stimulates saliva production to help the mouth stay moist, says Newhouse. She says saliva production sometimes decreases with age and about 500 commonly prescribed medications can cause dry mouth, which ups your chances of gum and teeth troubles.

Layliev suggests gums sweetened with xylitol, a natural sugar alcohol that acts as an antimicrobial and lessens inflammation. "Xylitol is also great because it satisfies sugar cravings without doing all the harm of true sugar," he says.