A surprising snack may help keep breath fresh.

A recent study reveals ordinary yogurt may help reduce hydrogen sulfide, an unpleasant-smelling compound that contributes to mouth odor. Look for plain, sugar-free varieties that contain live active cultures to help keep bad breath away.

Yogurt is a tart-tasting, semi-solid dairy product made from fermented milk. Eating yogurt helps support gastrointestinal health because it contains beneficial bacteria that aid digestion. Diarrhea or antibiotic use can deplete the body of these helpful microorganisms. Eating yogurt that contains live active cultures (LAC) helps replenish beneficial bacteria. A new study suggests eating about 3.5 ounces of plain, sugarless yogurt twice per day can reduce mouth odor by decreasing oral levels of hydrogen sulfide. To make sure your yogurt contains live active cultures, look for the LAC seal on the label and avoid yogurt that is heat-treated after culturing; this process kills the beneficial flora.