7 Wicked Winter Health Myths

Winter can be a pain. At its mildest, the chilly weather strains your lungs during your morning run. At its worst, it wields an icy grip on your arteries. "Cold air constricts your blood vessels," says John Elefteriades, M.D., chief of cardiac surgery at Yale Medical Group. "This helps keep your body warm—bloodflow just beneath the skin diminishes, so less heat escapes." But it also causes blood pressure spikes, which can stress arteries and heart muscle. So it's no surprise that deaths from heart attack, heart disease, and stroke peak from December through March.

But the subzero season's frosty reception isn't entirely weather-related—or deserved. These seven myths about the health perils of winter rank up there with the abominable snowman. So our experts will help you stop worrying about stuff that doesn't really matter so you can focus on things that do—all to keep you and yours healthy through the season. Now hit the slopes!

Allergies Hibernate in the Cold

You waved off ragweed in the fall, so you're done wheezing for the next few months, right? Maybe not. "People tend to focus on pollen and hay fever as the limit of their allergy risks," says John Santilli, M.D., an allergist and immunologist in Bridgeport, Connecticut. Mold and dust-mite allergies in the fall and winter are more common than you'd think.

Start with that fresh evergreen you haul into your living room every December. Mold spores can cling to the tree and multiply indoors. In a 2007 study, Dr. Santilli set up a real Christmas tree in a home and found that mold counts increased fivefold after 2 weeks. "It's like bringing a pile of leaves into the house," he says. "Even if you aren't allergic, the mold could still cause irritation, leading to upper respiratory or sinus infections." Decorations stored in a damp basement or attic are also sources of mold and dust mites. The fact that you close up your house in cold weather doesn't help either. "Closing windows and turning up the heat recirculates air and raises dust that had been collecting all spring and summer," says University of Arizona pulmonologist Paul Enright, M.D. And if you think that allergies are something you tend to outgrow—instead of something you can grow into—check out the 3 allergies that strike adults.

Your new strategy: Shake out the bad stuff

If only a live tree will do, chop one down at a local Christmas tree farm. "Decay doesn't start until a week after the tree is cut down," says Dr. Santilli. Ask the farmer if he has a tree shaker, which can help free any mold spores, loose pine needles, or lingering pollen. You can also blast your greenery with a leaf blower at home. Before bringing it inside, wipe off the tree's trunk with a 20-to-1 water-to-bleach solution to kill any mold, the Asthma and Allergy Foundation of America recommends. After the holidays, pack decorations in airtight plastic tubs to block out mold and dust mites. (Cardboard encourages mold growth.) Finally, install a HEPA filter in your HVAC system. These can remove up to 99 percent of dust and other particles, Dr. Santilli says.

Learn about the 8 most common food allergies.

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