The temperature just before dawn a couple of weeks ago was 34 degrees, with an intermittent wind out of the west. Being determined to get in a bike ride before settling down to work, I suited up: Capilene base layers top and bottom, UnderArmour ColdGear pants, a thick zip-up hoodie, an Eddie Bauer down jacket, super-insulated mittens, and a bike helmet.
Feeling like a kid in a snowsuit, I pedaled along the Arkansas River Trail toward Burns Park. The first person I encountered, a runner, was heading east. He was wearing shorts and a T-shirt.
Sure, runners burn up more energy than I do on my admittedly leisurely cycling outings. But still, how can humans have such different reactions to chill?
Varied reactions to cold are common, according to Australian physiologists Duncan Mitchell, Andrea Fuller, and Shane Maloney. “Some healthy people can feel colder than do others in the same environment,” they write in The Conversation.
“When you feel cold, blood vessels constrict, keeping blood away from the skin and closer to core organs, thereby conserving heat,” writes Devrupa Rakhsit on the website theswaddle.com. “So anything that interferes with circulation can influence to what extent we feel hot or cold when others don’t.
“Anything that affects our metabolism–the process of converting food to energy–also affects our perception of temperature. Often, women have a lower metabolic rate than men do, which means their bodies produce less heat, making them feel colder.”
But, the Australian physiologists explain, “Most of us who are healthy but claim to feel excessively cold have only ourselves to blame. We have habituated ourselves to feeling comfortably warm. In the developed world we rarely expose ourselves to cold, letting expensive clothing protect us from outdoor cold and letting power companies warm our living and working spaces.”
Besides, there’s a big difference between feeling cold and being cold. “Being cold is dangerous,” according to Ashleigh Costanza on the website weathernation.com. “When the body temperature lowers even just slightly, hypothermia can set in and severe damage to the body can occur.
“Feeling cold can happen while your body temperature remains within the realm of safe temperatures, but outside influences make you feel cold.”
Here are eight reasons why:
The more fat you have under your skin, the better insulated you are from winter’s bitter bite.
When you get older, your body isn’t as good at regulating temperature.
Women are more prone to feeling cold than men. A different genetic makeup makes it more difficult for women to regulate body temperature.
Along with girth, height plays a major role. A taller person will have a harder time with circulation because blood has farther to go. That same person also has more surface area to be affected by cold than a shorter person of the same build.
Everything from metabolism to stress to reduced brain activity can lead to your body not regulating heat very well.
Drink more water. It helps you regulate your body temperature.
Increased muscle mass will do everything from increase your metabolism to add a thick coat of insulation.
Anything from thyroid problems to diabetes to an iron deficiency can keep you chilled.
Well, thanks for the causes. How about some solutions? WebMD offers these, with varying degrees of usefulness:
Toss your clothes into the dryer before getting dressed.
Eat at least one hot meal a day, concentrating on foods that provide you with iron (poultry, pork, seafood, chickpeas, green leafy vegetables) and Vitamin B12 (chicken, eggs, fish).
Wear socks and flannel pajamas to bed. If you stay warm overnight, the sensation will stick around longer the next morning.
Dress in layers (see opening paragraph).
Or you can adapt. Humans can train themselves not to feel the cold, writes Amy Fleming in The Guardian.
She quotes Christopher Minson, a professor of human physiology at the University of Oregon: “Absolutely, people can adapt progressively to cooler temperatures. Humans have become very thermostatic. We go from our perfectly heated or air-conditioned house to our perfectly heated or air-conditioned cars to our perfectly heated or air-conditioned work.”
This, he believes, is not healthy. We’re not exercising the mechanisms we use to keep warm, and our perception of acceptable temperatures has become unnaturally narrow.
It is possible to train ourselves out of our thermostatic ruts, and Minson is constantly experimenting on himself, Fleming says. As it got colder one winter, he wore progressively warmer jackets to cycle to work. “I still saw people wearing just a T-shirt,” he says. So one day he decided to copy them. “The first few days were like: ‘Wow, it’s really cold,’ but within less than a week it got easier, and after a couple of weeks I could ride with my arms exposed and not feel as cold.”
Minson is a big fan of cold blasts in the shower too, Fleming reports. He started out by turning the shower to cold for 15 seconds, then increased it to 30 seconds until he could tolerate what he calls “a one-minute cold blast. It’s miserable for a while, but you do adapt. After doing that for a month or two, I started finding that when I was in cold environments I felt less cold.”
So it’s my fault that I feel cold. Should I gain weight, get younger, eat better, and start biking in cropped tights and a lightweight hoodie, followed by a bracing drenching of cold-water showering?
I think I’ll stick with the UnderArmour. And stop expecting others to mimic me.
Karen Martin is senior editor of Perspective.