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If you don't floss, you miss cleaning about 40 percent of each tooth, which can lead to tooth decay, Dr. Roizen says.

According to Dr. Levine, only 10 percent of Americans are flossing regularly, a very low number considering it's one of the most important things we can do for ourselves. Proper flossing contributes to good gum health and lowers the risk of heart attacks, among other problems.

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