7 Health Myths Your Doctor Wishes You Didn't Believe

Not necessarily, Collins says. Viruses do tend to be more active in cold weather, but a down coat won’t protect you if you’re run-down and haven’t been taking care of yourself. She says that you can catch a cold from staying inside in cold weather, especially if there are lots of other people around. Here's why: When it gets chilly outside, we tend to crowd indoors and crank up the heat. Collins explains that this causes the mucous membranes inside our nose to become dry and cracked, making us even more vulnerable to germs being passed around by family members, friends and coworkers. Collins adds that regularly exercising outdoors has a protective effect on our immunity, even when the weather outside is frightful. Just be sure to wear the right layers: Dress as if it's 10 degrees warmer than it is (you'll feel chilly to start, and comfortable after about five to ten minutes of moderate intensity).

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