While you may or may not have heard that answer before, there are concrete reasons for flossing. First of all, your toothbrush can't reach all the nooks and crannies (under your gumline and between your teeth). If you could look through a microscope to see what exactly is in the stuff that stays in your mouth (plaque) when you don't floss, you'd be surprised. And not happily surprised, either! Plaque is full of bacteria. In fact, not only can it cause you to have cavities, it can make you sick. Recent studies blame plaque for some cases of pneumonia, digestive illness, and even heart disease, not to mention bad breath!

When you floss, you can eliminate the bad breath, and you can cut your risk of getting sick.

To see a demonstration of good flossing technique from the American Dental Association, click here.