Myths and Tips About Dressing for Winter
Do you know enough about the cold to keep warm?
Poor planning of a winter outing can lead to frostbite and hypothermia. The following are some misconceptions about the cold, and some suggestions for staying toasty this winter.
Myth: Dressing warmly avoids cold, virus, flu
Mom was wrong on this one -- mostly. If you haven't been exposed to a virus, cold weather won't make any difference.
Robert Pozos, Ph.D., director of the thermal division at the Naval Health Research Center in San Diego, has put this theory to the test. He led a study in which researchers immersed 250 medical students in cold water until their body temperatures dropped to 95 degrees -- the point at which hypothermia begins. Some subjects got dehydrated and suffered slight cases of constipation, but none of them caught colds or viruses.
The researchers did find out that the body's defenses go down if the body is worn out. One student pulled an all-nighter before going to the laboratory. His body temperature dropped much more quickly than the others, Dr. Pozos says.
"The body has tremendous resistance," Dr. Pozos says. "People who get sick after being in the cold are already pretty sick anyway. Cold is just another stressor that can reduce resistance, like mowing the lawn or opening up your mail and finding out you owe income taxes."
Myth: You lose body heat through your head
There's nothing special about your head. You'll lose body heat from any part of your body that is exposed. It's a good idea to wear a hat, but other parts of your body must also be covered to keep you from getting cold, experts say.
The amount of heat you can lose through your head depends upon a number of factors, including how thick your hair is and how much energy you expend in the cold. You can expect anywhere from 5 percent to 55 percent heat loss from the head. The ratio of the surface area of a child’s head relative to the child’s body surface area is much greater than that of an adult so children lose proportionally more heat through their head. Hoods and hats are more important in children because of this.
Myth: Men, women feel cold at same temperature
Ever notice that women's hands and feet tend to get colder before men's? It's because the external temperature at which men's and women's bodies begin conserving heat -- called the set point temperature -- varies by about three degrees.
When surrounding temperatures drop to a certain point, your body will conserve heat by shutting off the blood flow to the hands and feet, making them feel chilled. For women, that temperature is about 70 degrees, while men can hold steady until about 67 or 68 degrees.
Myth: Dress in layers to stay warm
It's true that dressing in layers allows people to adjust for different levels of activity. But one well-made, warm garment will do just as well to keep away the winter chills, Dr. Pozos says.
"In the old days, people didn't know about dressing in layers," Dr. Pozos says. "They wore big old parkas instead." A good all-purpose garment might be a parka made of real animal fur, wool or a good synthetic material, says Dr. Pozos.
Dressing in layers does have merit, particularly for someone exercising in the cold, he adds. For the best results, he suggests wearing polypropyline or another synthetic fabric next to the skin, a knit middle layer (which can be taken off if you get too warm) and a synthetic outer layer.
Myth: Cotton is a good insulator
Don't drag those old cotton long johns out of the closet yet. They may be comfortable for lazing before a fire, but they can be downright dangerous outside in the cold.
When cotton gets wet, it conducts heat away from the body at a much more rapid rate than other fabrics, says Andrew J. Young, Ph.D., an exercise physiologist with the U.S. Army Research Institute of Environmental Medicine in Natick, Mass. Anything that can dampen your clothes -- such as perspiration, rain or falling in the water -- can cause cotton to start robbing you of heat fast.
A good substitute is polypropyline, capilene or some other synthetic substance that pulls water away from your skin.
Myth: Drinking alcohol will keep you warm
Drinking alcohol may make you feel warm because it causes blood to rush to your skin's surface. But it actually causes your blood vessels to dilate and makes you lose heat faster. Drinking alcohol in the cold also impairs the shivering process, which generates extra body heat.
But the worst part about alcohol consumption is that it impairs judgment. In a study of 10 emergency rooms across the country, 85 percent of hypothermia cases were related to drug and alcohol use, Dr. Pozos says. "It gives you a false sense of security, and then you end up doing something stupid," he says.
Myth: Fake fur as warm as real fur
Sorry, animal lovers. If you are going for one garment when you dress for the cold, animal fur is the best insulator, working much better than fake fur. Real animal hairs keep heat from leaving the body, and the leather of the fur is designed by nature to absorb heat, experts say.