We associate winter with spending more time at home because of the cold. But, we have been using the cold to heal ourselves for centuries. The Egyptians used cold water to reduce inflammation, British monks used ice as an anaesthetic, and an English doctor, James Arnott, used a mixture of ice and salt to relieve headaches or cancer tumors. Then in 2000 Japanese researchers asked a group of women to go for a walk in the cold in a miniskirt for a year and another group of women to go for a walk in an ankle-length skirt. The miniskirt group developed a new thin layer of fat on their legs. Until now it had been believed that only hibernating animals and babies had this layer. About 10 years later, American researchers discovered that this layer is brown fat or BAT (brown adipose tissue), a type of cold-inducing fat.
BAT is not harmful, on the contrary, it burns fat better than anything else, even muscle tissue. This explains how more active people have more brown fat than more sedentary people. Additionally, our cells are full of mitochondria, which convert the food we eat and the oxygen we breathe into a type of energy, adenosine triphosphate (ATP), which supports every cellular process in our bodies.
Brown fat serves to keep us warm and breathing. If we experience cold suddenly, it serves to increase our metabolism, regulate our appetite and improve our insulin sensitivity, which prevents the premature death of our cells. Simply put, brown fat makes our bodies repair themselves better. People with more brown fat are less likely to suffer from hypertension, congestive heart failure, and coronary artery disease.
The cold also helps keep our brains in good condition. We think more clearly when it’s cold. Our brains use glucose, so when we have less glucose, the brain works slower. We use more glucose when we cool down and less when we warm up, which explains why we feel slower in hot weather and more alert in cold weather. Israeli researchers have even discovered that simply looking at images of winter landscapes allows our brains to function more rigorously.
What’s more, the cold is good for our mental health. Polish researchers discovered that after spending 15 minutes in a cold, leafless forest, a group of students felt quite revitalizing, emotional and restorative effects. In 2018, researchers in Luxembourg continuously applied cold to the necks of volunteers. It activated their parasympathetic (calming) nervous system, which had the effect of reducing or stabilizing the speed of their heart rate, or rather, reduced their stress levels.
In addition to the beauty of autumn and winter, we become more resilient, because in the cold our hearts don’t have to work as hard and we sweat less, which means our bodies work more efficiently.
It is recommended that a 2-hour walk in the cold is enough to convert white fat into brown fat.
Don’t worry if you hate the cold. Many studies show that the cold becomes less intimidating the more you are exposed to it. It’s called ‘habituation’. It is recommended to wear more layers of clothing and take longer and longer outings to get used to it. And the brown fat begins to activate at 16ºC.
More and more studies show that more activity in the cold helps reduce allergic inflammation in the airways and relieve respiratory symptoms in adults, which is good news for allergy and asthma sufferers.
Carry a thermos with a hot drink. It is believed that caffeine also activates brown fat.
And finally, enjoy the changes in the landscape and nature as your brown fat develops.
Source: 52 ways to walk -Annabel Streets – Bloomsbury Publishing