Brushing seems like a no-brainer, but it's crucial, and experts say many of us aren't doing it correctly. First off, brushing isn't just about clearing food particles from teeth, so a few quick swipes won't cut it, says Dr. Nancy Newhouse, president of the American Academy of Periodontology. "The main purpose is to create friction on the tooth surface to remove bacteria and plaque," she says. This means two minutes of solid brushing, which most of us don't come close to reaching. "Spend a lot of time focusing on the tooth-gum junction," says Newhouse, adding that you should only use soft-bristled brushes. "Medium and hard bristles are way too abrasive and completely destructive to the gums," she says.

Timing is also key. Ideally, you should brush in the morning and at night, but Newhouse says the before-bed brush is more important, because we don't drink throughout the night, except for maybe a little water, and our mouths produce very little saliva to flush away bacteria. Also brush after meals whenever possible, but don't devour your lunch and then whip out the toothbrush. "Wait for about 30 minutes after a meal before brushing," says Dr. Emanuel Layliev, of the New York Center for Cosmetic Dentistry. "After eating, the pH in your mouth is very low, meaning it's a very acidic environment, so brushing immediately can wear down the teeth and gums even more."

If you can't brush during the day, then at least find a minute to floss after you eat, Layliev says. But never jab your gums with a toothpick, which damages gum tissue.