Wim Hof, a 57-year-old who goes by the nickname “The Iceman,” holds 20 Guinness World Records for withstanding extreme temperatures. He’s run barefoot marathons in snow, dunked himself naked in freezing lakes, and climbed Mount Kiliminjaro dressed only in shorts. Today, he instructs classes in the Wim Hof Method to students like surfer Laird Hamilton, claiming that exposure to cold, meditation, and special breathing techniques can essentially hack our immune and nervous systems, shedding pounds and improving health and energy.

A few years ago, investigative journalist Scott Carney flew to Poland to meet Hof, planning to expose him as a charlatan or madman in a piece for Playboy. “He seemed to be claiming superpowers,” recalls Carney. “Like conquering the world’s tallest mountains with no cold-weather gear, controlling his body temperature and immune system at will. I’d built my career debunking men like him.”


[quote position=”left” is_quote=”true”]Our lifestyles are just too antiseptic and comfortable now.[/quote]

Instead, Carney says that he dug into the science driving Hof’s health claims and found that he was the real deal, zeroing in on simple but profound techniques that allow us to turn the extremes of our environment to condition our bodies and renew our lost evolutionary strength. After meeting Hoff, Carney says, “I hiked to the summit of Mt. Kilimanjaro without a shirt. I sat on the snowy bank of a river until the ice melted around me.”

After turning his experience into the book What Doesn’t Kill Us: How Freezing Water, Extreme Altitude and Environmental Conditioning Will Renew Our Lost Evolutionary Strength, out this month from Rodale Books, Carney spoke to GOOD about just how healthy it is to go extreme.

In 2013, you first flew to Poland to meet Wim Hof as a skeptic. Can you tell us about those early days?

I was living in Long Beach, California, had a belly paunch, backaches, and thought my days of youthful adventure were fading fast. Then I saw a picture of a nearly naked man sitting on a glacier. I thought maybe Hof had some very special physical abilities—perhaps genetically bestowed—to be able to endure the ice. But when he started suggesting he could teach people the same techniques, I was wary. I didn’t go to meet him with the intention of changing my health. I went to expose him as a charlatan. But instead I learned that his techniques are teachable, and that he has unlocked some ways for us to use the environment to stimulate our innate immune system.

In your book, you talk about the scientists who have studied Hof’s abilities. What did they find out?

In 2007, at the Feinstein Institute for Medical Research on Long Island, Hof was studied by Kenneth Kamler, a doctor who has worked on Everest. Hof was connected to heart and blood monitors and immersed in ice. Hof stayed in the ice for 72 minutes. His heart rate went down to 35 beats per minute. His breathing slowed down to once every few minutes. His core temperature initially declined a few degrees, but then rose again. Later, Peter Pickkers, a research scientist at Radboud University Medical Center in the Netherlands administered a harmless toxin (one made by the common E. coli bacteria found in our gut) to Hof. Ninety-nine percent of healthy people react with flulike symptoms to the toxin before their body realizes it is actually not harmful. Hof did not react with flulike symptoms, he had only minor headaches. Blood drawn while he was meditating remained resistant to the toxin for six days after it had left his body.

You point out that Hof might have unique abilities, perhaps some of them genetically bestowed.

Hof’s ability to withstand long exposure to cold might be partly due to the fact he has larger than usual amounts of heat-generating brown fat. His identical twin brother André also has the same high amount. They were both studied by scientists in the Netherlands.

But he was actually able to train volunteers to regulate their immune systems, right?

Yes, he trained twelve healthy volunteers in his method. They received injection of the toxin, and the trained volunteers were able to keep the body’s reaction at a far lower level than their untrained counterparts. An anti-inflammatory molecule called interleukin-10 increased more rapidly in the trained volunteers, while inflammatory molecules were lower.

How would you describe your health today, after learning Hof’s method?

I can’t claim that what I’ve experienced will apply to anyone but me, but my metabolism has changed pretty radically. I used to wear size 36 pants and now I wear size 31. I was given a treadmill test by Rob Pickels of the CU Sports Medicine and Performance Center in Boulder, Colorado. My bloodwork showed that when I exercise, I burn fat, not carbohydrates. I’ve added the equivalent of seven hours of exercise to my weekly routine, but actually my total exercise is about three hours a week. I was always afflicted by painful mouth canker sores, since I was a kid. After using Wim’s cold-exposure techniques, I haven’t gotten a single canker sore. That’s a small thing, but I’ve met people who have reversed rheumatoid arthritis or Crohn’s disease using his approach.

What is the scientific explanation for all of this?

We have this underlying biology that’s very adaptable and survival-oriented, but these days we are cocooned in comfort and we don’t activate it. So we’ve broken our fundamental biological links to the world around us. Indoor plumbing, heating systems, grocery stores, cars, and electric lighting now let us control our environment so thoroughly that we can live in perpetual homeostasis. But we evolved differently. We evolved to survive variations in our environment.

[quote position=”right” is_quote=”true”]In one study, overweight diabetic men were put into a cold room and their insulin resistance improved.[/quote]

Think of our ancestors who mounted expeditions across frozen mountains and parched deserts with only a whisper of technology to aid them. Simply reintroducing some common environmental stressors can bring back some of our lost evolutionary vigor. There’s a hidden biology we can tap into. We need environmental and physical variations that invigorate our nervous systems. We are living today with an evolutionary mismatch. Ray Cronise, a former NASA scientist, says we’re overlit, overfed and overstimulated.

What does cold do for us?

First, it activates and increases your brown fat (BAT). BAT is a type of fat that the body uses to generate heat. So brown fat boosts our metabolism and burns calories. It stimulates your body to generate more muscle mitochondria, the energy powerhouses inside your cells. In one study, overweight diabetic men were put into a cold room and their insulin resistance improved.

Why would someone’s immune system improve?

We don’t have all the science yet, but I can speculate that it’s because your nervous and immune systems are connected. That’s been proven scientifically, and we also know it from the simple fact that when you’re in better spirits it’s harder to get sick. But if you’re depressed and stressed you’re likelier to come down with a cold. The way I look at it, our lifestyles are just too antiseptic and comfortable now. These cold showers and strenuous breathing techniques essentially give our immune system something to occupy it so it doesn’t turn on itself.

[quote position=”full” is_quote=”true”]You have to realize that your fear around this momentary discomfort—a discomfort that will definitely be there—is mostly in your mind.[/quote]

What is your routine these days?

I do his deep-breathing routine for 15 minutes every morning. The technique is outlined in my book, but it involves multiple rapid breaths followed by breath retention. I do 50 pushups while holding my breath. When I get in the shower, I expose myself to one minute of cold water at the end. The intensive cold shower or ice water activates your nervous system immediately. I keep the temperature of my home in the low 60’s. Just keeping the temperature of your home low is like doing a low-grade workout all the time. Your body has to work a little to keep warm. You can actually lose weight by dialing your thermostat down like that. And I run outside shirtless two or three times a week, no matter the temperature.

How did it feel climbing Mt. Kilimanjaro in shorts?

It was awesome and exhausting, but very liberating. The interesting part is not being shirtless. The interesting thing is the speed at which we did it, which was five times faster than the normal ascent. We did it in only 28 hours. Usually people go slowly because they have to acclimate to the altitude change. The peak is around 18,000 feet. Forty percent of climbers fail because of acute mountain sickness. In fact, some mountaineers called our climb a suicide mission. But the key was that we compensated with Wim’s breathing method. His method increases the rate of respiration and adds more oxygen to your tissues, and we did the breathing technique long before we had to. So we had enough oxygen in our systems to quickly climb. If you apply that concept to regular exercise, you want to breathe heavily before you get to the maximum exertion, before you feel you have to catch your breath.

In your book you say, “I don’t like to suffer. Nor do I particularly want to be cold, wet, or hungry. If I had a spirit animal it would probably be a jellyfish floating in an ocean of perpetual comfort.” Most of us are like you. What do you say to those who’d like to feel healthier, but shiver at the mere thought of getting icy water?

You have to realize that your fear around this momentary discomfort—a discomfort that will definitely be there—is mostly in your mind. If you’ve gone through your whole life and never been exposed to big temperature variations, then experiencing cold is going to be like going to the gym your first time. Of course it’ll hurt—I’m not going to sugar coat that for people.

But what’s exciting is that you’re suddenly opening your body to a new type of experience, and you will see very rapid changes in your physiology. Pretty quickly you’ll start to feel euphoria as you release all these hormones like cortisol and norepinephrine. It’s like a runner’s high. It’s a natural response.

What’s your final takeaway?

No environmental extreme induces as many beneficial changes in human physiology as the cold does. Use it.

  • How couples divide chores may shape sexual desire in ways you wouldn’t expect
    Photo credit: CanvaPeople cleaning at home.

    As many couples aim for more equal partnerships, dividing responsibilities isn’t always straightforward. In households where both partners work full-time, figuring out how to share chores has become an important part of maintaining balance at home.

    A new study published in The Journal of Sex Research examined whether couples dividing household chores is linked to a woman’s sexual desire. The researchers found that the relationship between the division of household labor and sexual desire varies based on beliefs about gender roles.

    cohabitation, domestic labor, relationship satisfaction, desire
    A couple cleans together.
    Photo credit: Canva

    Household labor balanced against sexual desire

    This pattern has long been explained in narrow ways. Low sexual desire among women in long-term relationships is often treated as an individual issue: stress, relationship dissatisfaction, or hormonal changes. Instead, this study examined a broader social dynamic: how work is divided at home compared to perceptions of what that balance should look like.

    Focusing on two different survey samples, the researchers found that women generally reported lower sexual desire than men while also indicating that they perform more household labor than their male partners. Mothers who took on a greater share of household responsibilities reported the lowest levels of sexual interest.

    The study also examined the impact of benevolent sexism, which refers to beliefs that reinforce traditional gender roles, such as women as caregivers and men as providers. A couple’s attachment to these beliefs significantly influences how household labor and sexual desire are connected.

    dual income, inequality, romance, marriage
    A woman is cleaning while her child plays.
    Photo credit: Canva

    Belief systems sway the balance of sexual motivation

    Women who held more egalitarian beliefs and preferred equal partnerships reported the highest levels of sexual desire when chores were split evenly. But when they found themselves doing a greater share of the household labor, they reported the lowest levels of sexual motivation.

    For women who endorsed more traditional gender roles, the pattern was different. In those cases, taking on more household responsibilities was not associated with the same decrease in sexual desire.

    Leading the research was Alexandra Liepmann, a PhD student in the Department of Psychology and Neuroscience at the University of Colorado Boulder. “Although women who endorse more traditional gender roles may not experience these costs in their sexual desire for their partner when doing more household labor, they may still experience costs in their personal and professional lives,” Liepmann told PsyPost.

    partnership, couples, division chores, relationship satisfaction
    Husband and wife are working from home.
    Photo credit: Canva

    Studies that connect the dots

    Adding to the evidence of this imbalance was a 2023 study focused on the distribution of household labor. It found that many relationships still adhere to unequal standards for women’s responsibilities compared to men’s.

    Another 2023 study found that women’s sexual desire tends to be more sensitive to the context of a relationship, particularly how things are going at home. This supports the idea that a woman’s perception of expected equality can affect her level of desire.

    Taken together, these findings indicate that household labor and beliefs about fairness may directly affect sexual desire for some women. Couples who divide chores more evenly may experience better intimacy outcomes regardless of their personal beliefs about gender roles and responsibilities.

  • 59% of Americans worry about sunscreen chemicals. Only 32% understand how sunscreen works.
    Two persons applying sunscreen while sitting on a beach.

    Tiffany Miller for Melanoma Research Alliance

    Many Americans think of sunscreen at the beach. Fewer consider wearing it for the drive there. And many are questioning if they should wear sunscreen at all.

    These trends, uncovered in a new national survey from the nonprofit Melanoma Research Alliance (MRA), highlight a central challenge in skin cancer prevention.

    Skin cancer is the most common form of cancer in the United States, according to the CDC. Nine in 10 skin cancers, including melanoma, are linked to exposure to ultraviolet (UV) radiation, according to the MRA. Reducing exposure to UV radiation lowers the risk of skin cancer, making sunscreen a key part of prevention.

    A survey of 2,000 adults found that most Americans have a basic understanding of the risks of sun exposure, but that awareness doesn’t always translate into action. More than 8 in 10 recognize that spending long hours in the sun contributes to melanoma risk, yet roughly one-quarter say they rarely or never use sunscreen when spending time outdoors.

    Then there are those everyday moments that most people don’t recognize as risky. The light coming through the window over the sink. The short walk from the parking lot. The hour in the bleachers with the sun hitting one side of your face. A single sunburn can be dangerous, but it’s the accumulation of exposure over time that often drives risk.

    Sunscreen is widely recognized as an effective tool for skin cancer prevention, yet confusion and misinformation persist, especially on social media. Fifty-three percent of respondents say they have seen claims that sunscreen ingredients may be harmful. Fifty-nine percent say they are concerned about what’s in sunscreen, and 38% don’t believe sunscreen is safe and effective.

    An infographic on Melanoma Research Alliance's surveys on sunscreen facts and usage.

    Many Americans also say they aren’t sure how sunscreen works. Only about a third can correctly explain the difference between types of sunscreens, while a much larger share reports being unsure.

    Sunscreen works by absorbing or blocking UV radiation from reaching the skin, preventing DNA damage that can cause skin cancer. In the United States, the active ingredients in sunscreen undergo rigorous review by the Food and Drug Administration, which evaluates them as over-the-counter drugs. This drug-level standard requires extensive testing and contributes to a more limited set of approved UV filters compared with Europe, where sunscreens are regulated as cosmetics. The FDA is currently evaluating additional methodologies for assessing sunscreen ingredients, a process that could expand the number of approved UV filters available to U.S. consumers.

    All of this is unfolding during a period of real progress in melanoma research. While melanoma remains the deadliest form of skin cancer, more than 8,500 Americans are expected to die from it in 2026, roughly one person every hour, according to the American Cancer Society. Recent advances are improving outcomes for many patients with advanced disease, though approximately 50% of patients do not respond to current treatments, according to MRA, underscoring why prevention and early detection remain critical.

    Survey methodology: The Melanoma Research Alliance commissioned Atomik Research to conduct an online survey of 2,000 U.S. adults between March 27 and April 1, 2026. The sample is nationally representative based on gender, age, and geography. Margin of error: ±2 percentage points at a 95% confidence level. Atomik Research, part of 4media group, is a creative market research agency.

    This story was produced by Melanoma Research Alliance and reviewed and distributed by Stacker.

  • You know exercise is good for you – so why is it so hard to put it into practice?
    Photo credit: Jordi Salas/Moment via Getty ImagesResearch shows that doing exercise around other people improves your chances of sticking with it.
    ,

    You know exercise is good for you – so why is it so hard to put it into practice?

    Laura Baehr Physical activity is one of the most powerful health tools people have to improve mood, energy and sleep, even after just a few sessions. But the real superpower of an active lifestyle is what it can do for health and quality of life over time. Scientific evidence repeatedly demonstrates that physical activity reduces the risk of developing chronic conditions…

    Physical activity is one of the most powerful health tools people have to improve moodenergy and sleep, even after just a few sessions.

    But the real superpower of an active lifestyle is what it can do for health and quality of life over time. Scientific evidence repeatedly demonstrates that physical activity reduces the risk of developing chronic conditions such as heart disease, diabetes and even some cancers. Despite this, most Americans are not getting enough physical activity in their daily lives.

    So why are so few people physically active when the benefits are widely known?

    As a physical therapist and rehabilitation scientist who studies how to boost movement for people living with chronic conditions and physical disabilities, I spend a lot of time thinking about that question.

    The short answer is that understanding the importance of exercise usually doesn’t translate into exercising. Making it a part of your lifestyle requires believing you can do it and knowing you can do it.

    Exercise is a lifestyle choice that helps reduce the likelihood of developing a chronic illness. But the good news is that if you’re one of the 194 million Americans already living with one or more chronic illnessesbeginning or maintaining an exercise routine can slow the progression, reduce symptoms and improve health outcomes.

    Side view of active senior man with dumbbells exercising at health club.
    It’s never too late to reap the benefits of being active. Maskot/DigitalVision via Getty Images

    The difference between knowing and doing

    People are perpetually being sold on the benefits of physical activity, whether it’s from national healthcare organizations, their medical teams or social media influencers.

    But research is clear that education alone does not predict changes in behavior.

    Instead, shifting your beliefs about the barriers preventing you from exercise might actually be the key to get you moving more.

    In 1977, a psychologist named Albert Bandura proposed that the ability to perform a task even when it’s difficult – a concept called self-efficacy – is the most important personal characteristic that drives healthy changes in behavior.

    Half a century later, self-efficacy is still considered one of the most crucial personal factors for behavioral change when it comes to long-term physical activity. Researchers who develop and test exercise interventions, including me, evaluate novel tools and programs that are built to boost self-efficacy.

    Someone with high self-efficacy might say that they can get back to their exercise routine even if they miss a day. Or they might find a way to still exercise when they’re busy or tired. Someone with lower self-efficacy might be thrown off their routine if presented with the same obstacles.

    But how do you build this crucial trait and get moving more? A meta-analysis found that despite its importance, there is not one magic way to boost self-efficacy.

    That’s because people’s behavior is more complicated than individual factors alone. People and groups have varying needs and contexts that require tailored approaches.

    Smiling Black woman in swimsuit holding onto rails in indoor pool.
    Doing exercise you enjoy is one key to consistency. Luis Alvarez/DigitalVision via Getty Images

    Tips increase exercise self-efficacy

    Self-efficacy may be affected by multiple factors, but people can still apply techniques to boost their ability to start and stay with an exercise routine.

    Make it manageable. It may seem intuitive to set personal goals, but many of us aim too high and end up discouraged. Goals focused on weight loss, heart health or muscle strength are fine, but they can take a long time to achieve. Long-range goals don’t tend to be motivating in the difficult moments – like when you want to hit snooze but promised yourself that you were going to take a long walk before work.

    Instead, try short-term goal-setting – such as aiming to get a set number of lunchtime walks in during the workweek. This will move you toward your long-term goals, while making it easier to see and feel progress.

    In 2026, the American College of Sports Medicine refreshed its guidance on strength training, which represents synthesized findings from 137 systematic reviews and the first update since 2009. The biggest recommendation difference? Consistency matters more than specificity of strength programs. What that means is that doing any strength training has health benefits as long as it is the kind you will keep doing.

    Make it add up. The CDC’s recommended 150 minutes of aerobic activity is meant to be spread throughout the week – not done all at once. Research shows that small bursts of activity still have significant impacts on your overall health, and you’re much more likely to stick with them.

    Only have 15 minutes while your kid is asleep? Have a short exercise video or app cued up for nap time. Waiting for your next Zoom meeting to start? Climb your stairs once or twice. Microwaving your lunch? Hold on to the counter and lift and lower your heels until the timer goes off. Every little bit matters to your mind and body.

    Make it meaningful. Prioritize doing things you enjoy. The gym is not for everyone, and luckily this style of structured exercise is just one of many options for physical activity. Go bird-watching, join a gardening group, binge watch your favorite show on the treadmill. Any activity you do that uses energy is like dropping a coin into your weekly physical activity bank.

    Make it more fun. Choose to be around people who are already exercising – and who encourage you to do it, too. Research shows that people who are sedentary will increase their physical activity by socializing with someone who is active.

    Another study shows that older adults can tap into the energy of their peers during group exercise, helping to build self-efficacy. Exercising with others can even reduce social isolation and loneliness. As a bonus, choosing physical activities you enjoy can improve your mood and boost your confidence.

    Overcoming the hurdles

    These strategies come with a very important caveat: Increasing self-efficacy is empowering, but context also matters.

    Some structural barriers to physical activity are beyond the scope of our individual motivation. Researchers and health professionals know that lower socioeconomic statusdecreased neighborhood safety and lack of access to exercise programs make being and staying active even more difficult.

    But the thing to remember is that even small improvements can have big impacts. It is consistent practice – not perfection – that is key to reaping all the benefits physical activity has to offer.

    This article originally appeared on The Conversation. You can read it here.

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