If you brush but don't floss, you're not cleaning 100 percent of bacteria out of your mouth -- in fact, you're missing 40 percent of it [source: Family Gentle Dental Care]. Brushing alone sweeps away plaque but only from the surface of your teeth. Floss removes it from between teeth and from under the gum line and is the easiest way to prevent gingivitis -- an infection that does more than irritate your gums. It can increase your risk of heart attack and stroke.
Gum disease is preventable, yet it's the No. 1 reason adults lose their teeth [source: Lewis]. Keep your teeth: floss daily, after meals.