We hate to burst your bubble, but the real secret to achieving fresh breath isn't chewing gum or sucking on mints -- it's flossing, says New York City-based dentist Jonathan B. Levine, D.D.S., author of Smile! The Ultimate Guide to Achieving Smile Beauty (Warner Books, 2006). "Using gum and mints will actually promote bad breath unless they're sugarless and alcohol-free," states Levine, adding that bacteria in your mouth break down sugar and alcohol into odor-causing by-products. Even the best sugarless options just mask odor for a few minutes. Another must-do: tongue cleaning, says Irwin Smigel, D.D.S., president of the American Society for Dental Aesthetics. Often overlooked, the tongue is also a potent breeding ground for bad-breath-triggering bacteria.