Your virus-protection plan needs an upgrade, and no, we're not talking about the one for your computer or smartphone. Studies show that the average person comes down with a cold two to four times a year and that up to 20 percent of the population gets the flu. Fortunately, there are now more effective ways than ever to kick your immune system into high gear. Here's how to fine-tune your healthy habits to fend off any nasty germs that come your way.
Healthy habit: You load up on plenty of colorful fruits and vegetables.
Power it up: Sure, vibrant-hued produce like kale and oranges have cold-fighting nutrients, but don't overlook their pale counterparts. White button mushrooms, for instance, can jump-start the body's natural killer cells, which attack cold and flu viruses, according to a study at Tufts University. "Mushrooms are abundant in a type of fiber, called beta-glucans, that can activate the