Your Ultimate Cold and Flu Survival Guide

The same live cultures that help ease digestive distress can help stave off a cold, says Dr. Phillips, who wroteThe Exhaustion Breakthrough ($20; amazon.com). A 2011 study backs this up: Scientists found that people who consumed probiotics via supplements or fermented foods (think yogurt, kefir and kimchi) had 12 percent fewer upper respiratory infections.

Spending the day in a stuffy room with anyone who's under the weather raises your risk of catching a bug. Letting a little fresh air circulate keeps airborne viral particles on the move, making them harder to pick up, says Dr. Phillips.

New research published in the Journal of the American College of Nutrition offered evidence of their immune-boosting powers. People who ate a cooked shiitake mushroom daily for a month showed higher numbers of T cells and less inflammation.

Sure, you hate to be rude, but moving out of firing range is crucial, says Dr. Phillips: "Germs carried in sneeze particles can travel 20 feet!" If a stranger next to you begins achooing or coughing, excuse yourself and scoot to another seat. All you need to say: "I'm sorry—I always catch colds really easily."

You might as well lick a restroom door (ick). "Not touching your face greatly cuts your odds of getting sick," says Margarita Rohr, MD, an internist at NYU Langone Medical Center. But that's easier said than done: The average person puts a hand on her mouth or nose more than three times an hour. To break the habit, try sitting on your hands when they're idle.

Take advantage of longer nights and log enough shut-eye. A study published in the Archives of Internal Medicine found that subjects who slept for fewer than seven hours were nearly three times as susceptible to colds as people who slept for at least eight hours.

For more ways to survive cold and flu season, click here.