Winter's here now, temperatures are dropping, and chances are that it'll get even colder. All that most of us want to do is cozy up indoors with a mug of hot tea and a heartwarming movie, but do cold temperatures bring us any health benefits? If so, what are they? We investigate.
I don't know about you, but I'm definitely what you might rather unscientifically refer to as a "summer person." I thrive in hot weather, love wearing light clothes, and cherish the long, sunny days that make me feel productive.
But in winter, I always complain about the cold, bundle up under five different layers of clothing, and grumpily wait it out until temperatures rise again. But am I wrong in being so dismissive of this season and the low temperatures it brings?
Research has suggested that cool temperatures could bring a range of health benefits, and that we shouldn't always shun exposure to cold. In this article, we give you an overview of some of these reported benefits.
The cold can boost sleep quality
Our bodies follow a circadian rhythm that self-regulates eating, sleeping, and activity patterns according to day-night cycles, thereby allowing us to function normally. Researchers have found that a dysregulation of circadian rhythms can lead to a disrupted sleep, which, in turn, can lead to a number of health problems.
Studies that were recently covered by Medical News Today have found that insomnia and other sleep disorders can impair our perception and cognitive function and heighten the risk of kidney disease and diabetes.
This is where external temperatures come in. One study experimented with "cooling caps" — that is, headwear that keeps the sleeper's head at cooler temperatures — and found that insomniacs benefited from the exposure, which allowed them to enjoy a better night's sleep.
Current sleep guidelines — supported by existing research — suggest that the ideal temperature in our bedrooms as we prepare to go to sleep should be somewhere between 60 and 67 degrees Fahrenheit (around 15.5 to 19 degrees Celsius).
The bottom line is that you shouldn't be freezing cold, of course — that won't really help your sleep — but moderately cool environments might do the trick.
It gives you an appetite
A study published in the European Journal of Clinical Nutrition seems to support the age-old claim that our appetite increases in winter, as the temperatures drop fast. "[T]he present study revealed that small seasonal variations of daily caloric intake, diet composition, physical activity, and body weight are in fact present in normal individuals in the United States," the authors conclude.
Another experiment carried out in pigs, which have a similar physiological makeup to humans, saw that the animals also tended to eat less in higher ambient temperatures, but their appetite increased in cooler environments.
Another study, this time exploring the impact of intense aerobic exercise and ambient temperature on caloric intake, found that being active in a cool environment stimulates our sense of hunger.
So if you're struggling with eating healthful portions, then a brisk walk or run in the cool winter air just before a meal could help to increase your appetite.
'Fat is on fire'
If, on the other hand, you're concerned that your tendency to eat more this season will lead to unwanted weight gain, worry not: the cold can also be used catalyze weight loss.
Our bodies store two types of fat: white and brown. The former is often referred to as "bad fat," as it simply accumulates. And, if it piles up excessively, it can lead to overweight or obesity. By contrast, brown fat is "good fat," as it is the fuel that our bodies burn for energy.
It's not surprising, then, that scientists are always on the lookout for ways to stimulate the body to turn its white fat reserve into brown fat. The main way of "browning" white fat that research has uncovered is through exposure to cooler temperatures.
In the cold season, our bodies will seek ways to keep warm, which requires dipping into the fat supply for fuel. One study published in The Journal of Clinical Investigation found that exposure to cold temperatures can activate brown fat metabolism in adult humans. This refers to moderate cold that is not accompanied by shivering.
The authors of the editorial that was published alongside this study explain that brown fat activity "is regulated from the brain, based on the need for heat for body temperature control."
"The heat," they continue, "results initially from combustion of stored lipid within the brown adipose tissue, but during prolonged [heat production], the components of ingested food are channeled to the tissue as a continuous supply of substrate."
Rather than being deposited, that is, fat is constantly burned to generate heat. The authors say:
"They [the study authors] demonstrate that brown adipose tissue in adult humans is actually metabolically highly active when it is stimulated physiologically, that is, even human brown fat is on fire."
Shiver your excess weight off
Moreover, shivering on its own also stimulates the burning of fat, researchers have shown. A study published in the journal Cell Metabolism found that shivering stimulates the secretion of irisin, a hormone that induces fat burning.
Apparently, just 15 minutes spent shivering in a cold environment has the same effect as exercising for an hour.
More daring entrepreneurs have devised a way to allegedly maximize the effect: wearing a vest loaded with ice packs. This vest, donned for an hour, is supposed to help the wearer burn up to 250 calories.
Yet even the vest's inventor emphasizes the fact that this device isn't a miracle worker, and you won't magically get fit without appropriate nutrition.
Inflammation and pain begone?
Another well-known benefit of exposure to cold temperatures is decreasing inflammation locally. Many of us will probably remember being told, when we were little, to apply an ice-cold compress to a head bump after a playground accident.
Traditionally, ice or a compress submerged in cold water have been used to treat a wide array of bumps and bruises, although we should be careful about how much cold we apply for each type of inflammation, and on each person.
"The amount of cold applied to the body should not outstrip the body's ability to neutralize it," writes naturopath Christopher Vassey, the author of Natural Remedies for Inflammation.
But some argue that immersion in cold water for the treatment of inflammation is not significantly more effective than other recovery options. Still, ice pops continue to be used when it comes to soothing a sore throat, as they numb nerve endings in the throat and reduce the feeling of pain.
Researchers from Johns Hopkins University in Baltimore, MD, advise that cryotherapy — which is a treatment relying on exposure to the cold — can be effective in reducing local pain, but they also note that it may be best if we use cold compresses in combination with medication and other treatments, as appropriate.
Unfortunately, for many people, the cold season is associated with low moods and a sense of fatigue, as they fall prey to seasonal affective disorder, a type of depression that usually manifests in winter. However, it's not all doom and gloom; research has shown that cold or unfriendly weather also have some surprising upsides.
A study from the University of Newcastle in the United Kingdom found that in bad weather — including cold days — we tend to make longer phone calls, but to fewer people. This means that when the weather puts us off from other activities, we tend to stay home or close to home and want to reconnect with the people who matter most to us.
Another study suggests that cold environments might promote a type of creativity that the researchers refer to as "referential creativity," based on "cold cues." Cool temperatures may render us better at recognizing metaphors, inventing new pasta names, and "being abstract in coming up with gifts," they say.
These examples may seem to be fairly useless endeavors in and of themselves — who needs to come up with new names for pasta? — but, according to the authors of the study, they suggest that low temperatures help us to overcome mental habits and think outside the box.
"Referential processing style situated in physically cold contexts," conclude the scientists, "largely benefits the kind of creativity that requires greater flexibility to switch between mental frames and to break set from pre-existing knowledge systems."
Since December has arrived and the winter holidays are just around the corner, now is your chance to grab your gloves and scarf and brave the cold in search of perfect Christmas gifts, or — why not? — a cup of mulled wine.
Then, after some quality time spent out in the cool air, why not come back to this article and let us know: how do you think cold temperatures benefit you?