With temperatures plunging into the basement of the freezer of Chicago’s winter, why is it that even some Windy City veterans are so incredibly cold? Or better yet, why is it that some of us aren’t?
"Some people deal better with the cold," says The University of Chicago’s Dr. Nadera Sweiss. "Some people can hold a can of soda in their hands and start shivering. And others may hold ice in their hands and not be affected."
Indeed, some animals, and in fact some human cultures spend the bulk of their lives in ice and snow. Every winter, thousands of fish swim happily under the ice of Lake Michigan.
"Fish are exothermic," explained Eve Poynter of Chicago’s Shedd Aquarium. "This means that they regulate their body temperature by the surroundings around them. So as the water decreases in temperature, their body decreases in temperature. And their metabolism slows down."
Some species of penguins also live out their lives frolicking in snow and ice.
"First of all they have a little bit of fat," said Shedd’s Lana Vanagasem. "And then they have a very dense under layer of feathers that keeps them warm, covered by a waterproof feather layer on the top."
Of course, the penguins have nothing on human cultures like the Inuit of far North America. Better known as eskimos, the Inuit and other indigenous peoples thrive in the cold.
"In the colder environments, people tend to have shorter, stockier frames to preserve the core temperature in their bodies," said Dr. Ryan Williams, curator and chair of the department of Anthropology at Chicago’s Field Museum. "Their limbs tend to be a little bit shorter, so that the blood doesn’t have to travel as far to keep those extremeties warm all the time."
Williams has conducted numerous expeditions to the high reaches of the Peruvian Andes, living for weeks at a time with the Aymara high above the snow line. He says they know it’s cold. It is simply part of their culture.
"They’ve domesticated animals that can provide them with warmth like the llamas and alpacas," Williams says. "People who live in those environments recognize it as entirely normal. This is how life is. They’ve adapted to it."
What about the rest of us? Why is it that two people in the same room can feel different temperatures? Those fights over the thermostat? Experts say they are not imaginary.
"Women tend to get colder than men," said Dr. Sweiss, who sees patients in the University of Chicago’s Cold Hands Clinic. But she said anyone who has recently developed a sensitivity to cold, may be showing signs of significant medical issues.
"Some of the common reasons for that are thyroid diseases, for the body to feel cold in general," said Sweiss.
Others can develop very serious issues with hands and other extremeties. Reynaud’s syndrome, which often manifests itself with cold and discolored fingers or toes, can lead to gangrene and even amputation of the fingers. For patients susceptible to Reynaud’s, Chicago’s cold can lead to intense pain.
Dr. Sweiss said some sensitivities to cold are less threatening, even if they are intensely uncomfortable. Thinner people tend to get colder than heavy people. Older individuals often feel colder than their younger counterparts.
Oddly, married women seem to handle cold better than unmarried women. Some doctors speculate the ability to deal with chilly temperatures could be genetic, or even governed by the climate where an individual grew up.
"What are the reasons for the differences, are not clearly understood," said Sweiss.