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They move more

Internist Kristine Arthur, MD, with the Orange Coast Memorial Medical Center in Fountain Valley, California, helps keep sickness at bay by staying in good physical shape. “I try to squeeze in exercise like walking throughout the day,” she says. “If there is a bathroom a bit farther down the hall or up one level, try walking to that one. Park further out in the parking lot. Take the stairs instead of the elevator.” Studies show that exercise can help boost your body’s ability to fight off infection. Avoid getting a cold or flu by adopting these habits that naturally boost your immune system.