Written by Beau DeCourcy
Some consider me a little crazy when walking in the dead of winter with just a t-shirt and jeans, or taking icy plunges into rivers while snow remains on the banks. “Are you trying to get sick?” they ask. My answer often puzzles them: “No, I’m trying NOT to get sick.” Conventional wisdom seems to suggest that going outside in winter without a hat and down parka is playing the odds of getting a nasty cold. Once again, conventional wisdom is not only off the mark, but just plain backwards!
Periodic cold exposure is one of the best ways to boost immunity, and reduce chronic inflammation. Being cold is stressful, and as we have learned thus far, periodic stressors, such as exercise, and cold exposure strengthen us. It is not the cold of winter itself that leads to increases in illness. This is important to understand: correlation is not causation. Meaning, just because two things occur at the same time (cold temperatures and colds) does not mean one causes the other. It’s more what is not as present in winter that causes increased illness: the sun. Sun exposure is vital to immunity through the production of vitamin D3. Not only do the days get shorter in the winter, but we cover every inch of ourselves up in a deliberate attempt to avoid a chill, inadvertently blocking the sun. It turns out you’re much better off getting a quick chill and some winter sun on your face and arms!
Compounding this increase in sickness during cold winters is the unhealthy food we tend to overeat around the holidays, which happen to conveniently fall right as the days get shorter and colder. Considering that vitamin C and glucose share the same transport pathway into the cell, sugary, processed foods are certainly a huge strain on our immunity. When you pack a bunch of vitamin D deficient people in one building for a sugar-cookie fest, the outcomes are probably not in favor of health.
Beyond physiologic improvements of health, there is emerging evidence that cold exposure treatment is effective in treating depression. Exposure to cold stimulates the release of beta-endorphins and other hormones that are powerful stress reducers. Interestingly enough, depression increases in the winter in the form of a condition known as SAD (seasonal affective disorder). A lot of people tend to treat their depression with culinary creations also known as junk food, further adding to the increasing incidence of cold and flu contraction. It seems, however, the best way to counteract the winter blues and illness is to get out and get cold for a bit each day.
From an ancestral perspective, the benefits of cold exposure make sense. Every one of us is a descendant of the hardy few of our ancestors that survived the ice age. We are genetically selected and capable to thrive in cold climates. In fact, we have specific metabolically active fat cells known as brown adipose tissue that function primarily to produce heat. Yes, fat burning fat cells! Periodic cold exposures (baths, showers, reduced clothing, etc…) increase the activity and density of these BAT (brown adipose tissue) cells. In addition to BAT, our muscles also contain the ability to uncouple from our metabolism (uncoupling proteins), allowing us to burn stored energy solely for free heat. These metabolic pathways target subcutaneous fat tissue primarily for heat production, thus making cold exposure an ideal method to your improvement of body composition.
Being cold is not pleasant, but you don’t need to plunge in to frigid water daily to obtain these benefits. Simply ending your shower on cold for a minute or two, or going on a brisk, cool walk can up regulate fat metabolism, improve immunity, and leave you feeling a little happier. Don’t fear the cold. Exercise comfort zoning and get outside year round. Challenge yourself to a cold plunge from time to time. Engaging in “thermal exercise” can make you healthier, leaner, and happier.
What is your experience with the cold? Would you consider periodic cold exposure to improve your health?