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Wash your hands

According to the Centers for Disease Control and Prevention, hand-washing is the number-one action you can take to dodge the 1 billion colds Americans come down with annually (not to mention the bacteria, such as E. coli and salmonella, that cause foodborne illnesses).

Make it work for you: Wash with regular soap and warm water for at least 20 seconds (the time it takes to sing "Happy Birthday" twice). Vigorously scrub all parts of your hands, not just palms, and check your fingernails for trapped dirt. Dry with paper towels, or designate a cloth hand towel for each member of your household.

Next: Take vitamin C and zinc