A major cause of bad breath, plaque, and gum disease is a
buildup of bacteria. But research has found that 6 ounces of
plain, sugar-free yogurt a day might help knock out germs
between teeth. "The good bacteria in yogurt may help fight bad
ones in your mouth," says Christine D. Wu, Ph.D., a professor of
pediatric dentistry at the University of Illinois at Chicago
College of Dentistry. It even works for toothbrush-averse kids:
Those who eat yogurt four or more times a week tend to get fewer
cavities, according to one study. To sweeten the plain kind,
stir in some honey, which also contains compounds that inhibit
bacteria.