Health Benefits of Cold Exposure

Updated: Jan 22, 2021

Cold-water guru Wim Hof has long extolled the virtues of exposure to freezing temperatures, and he's definitely on to something...

If you aren’t already committed to the Dutchman’s mantra that “a cold shower a day keeps the doctor away”, then you may have at least heard of some of his epic feats of cold exposure endurance but, extraordinarily, he's not an anomaly of nature. Scientists have meticulously compared his genetics with that of his more sedentary twin brother and found no differences.

A lifetime of following his own path, discovering yoga and pranayama as a teenager and then stumbling into his first blissfully cold swim aged 17 means that at the age of 61 he has more brown adipose fat (which breaks down blood sugar – glucose – and fat molecules, allowing the body to create heat) than a man half his age. During this time he has developed the eponymous Wim Hof Method, a combination of frequent cold exposure, focused breathing techniques and meditation.

Ten thousand years ago, humanity was rampaging around, hunting in little more than an animal’s hide. Now we wrap ourselves up in mountain-grade down jackets just to walk the dog. While it’s instinctive to avoid the cold, the outcome in today's world is that we’ve arguably retreated too far into the warmth and subsequently alienated ourselves from our psychology to the point where, as Hof says: “We think you’ve got to be tough to go into the sauna and the cold water, which isn’t true. It’s about bringing the cardiovascular system to its rightful condition. We are weakening ourselves.”

With lockdown restrictions on socialising at home or in the pub, we’ve all been spending more time in parks and woods, getting a taste of what the Norwegians call friluftsliv (“embracing the outdoors”), with the known benefits to our mind, body and soul, as well as our vitamin D levels and serotonin and melatonin production. However, if you’ve been wrapping up in endless warming layers, you will have been missing out on the benefits of cold exposure.

The positives of cold exposure are gradually being understood and endorsed by scientists - demonstrating how embracing the winter chill can help fight obesity, depression and illness.

Here's a quick summary of the science bit: the human body has its mechanisms for adjusting to the cold; the hypothalamus, which acts as the body’s thermostat, responds to signals from the skin by causing vasoconstriction of the blood vessels, reducing blood flow to the extremities to protect the core and prevent heat loss. Wearing a big coat means you are covering up the body’s thermoreceptors and inhibiting its ability to self-regulate temperature. By doing so, we miss out on exercising the muscular tone of the vascular system.

“And do you know who’s paying for that?” says Hof. “Our heart is. When these little vascular muscles are not tuned up, not working at an optimised condition, our heart is forced to pump much more, deeper and stronger, to get the blood flow through. This puts undue stress on our heart on a chronic basis. That’s one of the primary reasons, together with diet and exercise, why cardiovascular-related diseases are the number-one killer in our society.”

Hof might be a maverick but many scientists agree that our comfort behaviourism is contributing to poor health. Until recently, it had been assumed that brown fat decline was an inevitable part of getting old. However, studies have shown that we can regrow brown fat through cold exposure.

Dr Barbara Cannon, professor emerita of physiology in the department of molecular biosciences at the Wenner-Gren Institute, Stockholm University, Sweden, knows that brown fat is preferable to white fat (the latter being linked to obesity) and her research demonstrates that metabolism in brown fat is increased when adult humans are exposed to cold.

“If you’re out in the cold, you’ll have a response that’s rather like exercise, in that you’ll increase your heart rate,” says Dr Cannon. As a result, cold exposure has been hailed in some quarters as a weight-loss tool. Researchers around the world are working to harness brown fat’s activity in order to treat obesity, diabetes, and other metabolic disorders.

The link between cold exposure and immunity to infection is also being studied. Exposing yourself to limited stress is called hormetic stress exercising - the theory being that something that produces harmful biological effects at high doses produces beneficial effects at low doses. Seemingly, cold exposure can make the body more alert and prepared; and, it’s claimed, can boost our ability to fight infection.

A study at Radboud University Medical Center in the Netherlands took blood samples from Hof before and after his regimen of breathing, meditation and an 80-minute full-body ice bath, and found that afterwards he had reduced levels of proteins associated with the immune response. He was then injected with an endotoxin that would normally stimulate a rapid immune response. Most subjects responded with flu-like symptoms, with affected cells releasing cytokines. Hof, on the other hand, had no flu-like symptoms and half as many cytokines as control subjects. In a further study, he trained some volunteers in the Wim Hof Method for a week; they, too, had reduced symptoms.

The same year, Dr Marius Brazaitis, a scientist at the LSU Institute of Sport Science and Innovations in Lithuania, conducted a study where a group of healthy men spent three hours a day in baths filled with 14C (57F) water. By day 20, the men’s shivering, which is the human body’s initial response to cold, had more or less stopped. Their metabolisms and heart rates still sped up in response to the cold-water bath, but their blood vessels no longer constricted and their skin temperature didn’t drop the way it had before. Dr Brazaitis says his tests show that you have better circulation when you are exposed to the cold and, he told The Telegraph: “our subjects afterwards reported that, that year, they didn’t catch any colds. It seems that they had some sort of resistance to illness.”

Immunity has been the word on everyone’s lips during the 2020. Fortunately, we don’t have to have to go through the same level of discomfort to replicate some of the benefits. Hof has a far more accessible solution; “Cold showers!” He recommends ending a warm shower with 30 seconds of cold water. Gradually, your tolerance will lengthen, with Hof saying all of us should be able to last for two and a half minutes in a cold shower. He feels strongly that they are a powerful tool to support our immune system.

Meanwhile, at OGN Towers, one of our researchers tells us he has been taking a cold shower every morning for the last 5 years. And has not had a cold since.

The benefits of cold exposure don’t stop there. As well as stimulating metabolic activity and enhancing the immune system, when you are cold-acclimatised less adrenalin is released during exposures, meaning less stress and less inflammation. You also get a hit of dopamine, endorphins and serotonin. No surprise, then, that Hof is a strong believer that it can hold depression at bay, and is currently working with the University of San Francisco on a study relating to depression.

“With a little activation through the cold we are able to rebalance ourselves and we get a sense of control of ourselves again,” says Hof. “It makes sense because it feels so good.”

You may want to go deeper into the WHM method but, for most of us, even trying to turn the temperature down on the shower will be challenging enough. And that is OK. Cold exposure for you could be as simple as leaving the scarf at home. Because, as Hof stresses, it’s not about being tough, it’s about getting back into the natural conditions of our cardiovascular system.

Source: Telegraph