Nov. 6, 2011 -- Was Mom's Stay-Well Advice Right?
Don't go out with wet hair. Rest. Cover your mouth when you cough.
This "feel-better, don't spread colds" advice was recently put to the scientific test. The verdict: Most of our moms' classic tips won't keep us safe from colds and flu, says Rachel Vreeman, MD, an assistant professor of pediatrics at Indiana University School of Medicine and the author of the myth-busting book Don't Swallow Your Gum. But Mom did get a couple of things right. Here, experts set the record straight on which motherly advice is worth taking.
Tale: You'll get sick if you go out in the cold with wet hair.
The truth: Exposure to viruses—not skipping the blow-dryer—causes cold and flu.
"Scientists have studied this really well," says Vreeman. "They've put cold viruses in the noses of two groups of people. One group was then exposed to cold/wet conditions, and people who were chilled were no more likely to get sick than those who weren't." Being outside can make your nose run (cold weather dilates blood vessels), but it doesn't make you more susceptible to viruses.
Tale: Feed a cold, starve a fever.
The truth: This is half right.
When you're congested, nutritious food will fortify your immune system. But when you're feverish, your metabolism is revved up and you need more energy—not fewer calories—to fight off infection. Bottom line: Stay hydrated and eat well, no matter what your symptoms.
Tale: Avoid dairy when you have a cold.
The truth: There's no medical basis to skip dairy when you're sick.
Many people, including some pediatricians, believe that dairy products increase mucus production. However, research shows this may be a placebo effect. In one study, people who knew they were drinking cow's milk reported more nasal symptoms than those who had soy milk—but people who didn't know which milk they were drinking reported the same (minimal) effects.
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Tale: You lose most of your body heat through your head.
The truth: It's wise to keep your head covered with a cozy hat.
Although technically you don't lose more body heat through your head (about 10%, which is proportional to the body surface area)—it may feel that way, says Cleveland Clinic researcher Daniel Sessler, MD. That's because your face is about 5 times more sensitive to temperature than other areas. "It's an early warning system that alerts you to put on a sweater or turn up the thermostat long before your core body temperature gets too cold," says Sessler
Tale: Have some chicken soup when you're sick.
The truth: There's something to this age-old comfort food remedy.
Researchers from the University of Nebraska Medical Center found that chicken soup prepared with lots of veggies mitigates some of the inflammation responsible for cold symptoms, like a runny nose and congestion. To get rid of common cold symptoms, you have to get rid of the inflammation that's causing them, says Jack Gwaltney Jr., MD, a professor emeritus of medicine at the Center for the Prevention of Disease and Injury at the University of Virginia School of Medicine.
Tale: Rest, don't exercise, when you're under the weather.
The truth: You do need to rest, but a little exercise might help you feel better.
In a study from Ball State University, volunteers with severe colds were divided into two groups, one of which exercised for 30 minutes a day, 5 days a week. The other group simply rested. In both groups, cold symptoms lasted for about 8 1/2 days (8.36 for the exercisers; 8.45 for the resters) and peaked during the morning hours. But as a group, the exercisers felt better during the afternoon and evening than the resters did.
While some exercise is good for you, don't overdo it when you're sick. Intense workouts (lasting more than 90 minutes) can actually weaken immunity.
Tale: Cover your mouth with your hand when you cough.
The truth: Although this might look polite and germ preventing, it's anything but.
When you capture a cough or sneeze in your hand, you're likely to pass the cold on to someone else. Cold viruses exist in large quantities in the nasal fluid of sick people and are easily transferred from their hands after even the briefest contact. You also leave viruses on doorknobs, phones, countertops, and elevator buttons.
To sidestep such icky transmissions, be sure to wash your hands frequently, and use a tissue or, if one isn't handy, cough and sneeze into your inner elbow.
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