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.

  • Social media before bedtime wreaks havoc on our sleep − a sleep researcher explains why screens alone aren’t the main culprit
    Photo credit: Adam Hester/Tetra Images via Getty ImagesSocial media use before bedtime can be stimulating in ways that screen time alone is not.

    “Avoid screens before bed” is one of the most common pieces of sleep advice. But what if the real problem isn’t screen time − it’s the way we use social media at night?

    Sleep deprivation is one of the most widespread yet overlooked public health issues, especially among young adults and adolescents.

    Despite needing eight to 10 hours of sleep, most adolescents fall short, while nearly two-thirds of young adults regularly get less than the recommended seven to nine hours.

    Poor sleep isn’t just about feeling tired − it’s linked to worsened mental healthemotion regulationmemoryacademic performance and even increased risk for chronic illness and early mortality.

    At the same time, social media is nearly universal among young adults, with 84% using at least one platform daily. While research has long focused on screen time as the culprit for poor sleep, growing evidence suggests that how often people check social media − and how emotionally engaged they are − matters even more than how long they spend online.

    As a social psychologist and sleep researcher, I study how social behaviors, including social media habits, affect sleep and well-being. Sleep isn’t just an individual behavior; it’s shaped by our social environments and relationships.

    And one of the most common yet underestimated factors shaping modern sleep? How we engage with social media before bed.

    Emotional investment in social media

    Beyond simply measuring time spent on social media, researchers have started looking at how emotionally connected people feel to their social media use.

    Some studies suggest that the way people emotionally engage with social media may have a greater impact on sleep quality than the total time they spend online.

    In a 2024 study of 830 young adults, my colleagues and I examined how different types of social media engagement predicted sleep problems. We found that frequent social media visits and emotional investment were stronger predictors of poor sleep than total screen time. Additionally, presleep cognitive arousal and social comparison played a key role in linking social media engagement to sleep disruption, suggesting that social media’s effects on sleep extend beyond simple screen exposure.

    I believe these findings suggest that cutting screen time alone may not be enough − reducing how often people check social media and how emotionally connected they feel to it may be more effective in promoting healthier sleep habits.

    How social media disrupts sleep

    If you’ve ever struggled to fall asleep after scrolling through social media, it’s not just the screen keeping you awake. While blue light can delay melatonin productionmy team’s research and that of others suggests that the way people interact with social media may play an even bigger role in sleep disruption.

    Here are some of the biggest ways social media interferes with your sleep:

    • Presleep arousal: Doomscrolling and emotionally charged content on social media keeps your brain in a state of heightened alertness, making it harder to relax and fall asleep. Whether it’s political debates, distressing news or even exciting personal updates, emotionally stimulating content can trigger increased cognitive and physiological arousal that delays sleep onset.
    • Social comparison: Viewing idealized social media posts before bed can lead to upward social comparison, increasing stress and making it harder to sleep. People tend to compare themselves to highly curated versions of others’ lives − vacations, fitness progress, career milestones − which can lead to feelings of inadequacy and anxiety that disrupt sleep.
    • Habitual checking: Social media use after lights out is a strong predictor of poor sleep, as checking notifications and scrolling before bed can quickly become an automatic habit. Studies have shown that nighttime-specific social media use, especially after lights are out, is linked to shorter sleep duration, later bedtimes and lower sleep quality. This pattern reflects bedtime procrastination, where people delay sleep despite knowing it would be better for their health and well-being.
    • Fear of missing out, or FOMO: The urge to stay connected also keeps many people scrolling long past their intended bedtime, making sleep feel secondary to staying updated. Research shows that higher FOMO levels are linked to more frequent nighttime social media use and poorer sleep quality. The anticipation of new messages, posts or updates can create a sense of social pressure to stay online and reinforce the habit of delaying sleep.

    Taken together, these factors make social media more than just a passive distraction − it becomes an active barrier to restful sleep. In other words, that late-night scroll isn’t harmless − it’s quietly rewiring your sleep and well-being.

    How to use social media without sleep disruption

    You don’t need to quit social media, but restructuring how you engage with it at night could help. Research suggests that small behavioral changes to your bedtime routine can make a significant difference in sleep quality. I suggest trying these practical, evidence-backed strategies for improving your sleep:

    • Give your brain time to wind down: Avoid emotionally charged content 30 to 60 minutes before bed to help your mind relax and prepare for sleep.
    • Create separation between social media and sleep: Set your phone to “Do Not Disturb” or leave it outside the bedroom to avoid the temptation of late-night checking.
    • Reduce mindless scrolling: If you catch yourself endlessly refreshing, take a small, mindful pause and ask yourself: “Do I actually want to be on this app right now?”

    A brief moment of awareness can help break the habit loop.

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

  • It’s more than OK for kids to be bored − it’s good for them
    Photo credit: Richard Lewisohn/Connect Images via Getty ImagesWhen children experience boredom, it can result in a brain boost that can push them to explore new activities.

    Boredom is a common part of life, across time and around the world. That’s because boredom serves a useful purpose: It motivates people to pursue new goals and challenges.

    I’m a professor who studies communication and culture. I am currently writing a book about modern parenting, and I’ve noticed that many parents try to help their kids avoid boredom. They might see it as a negative emotion that they don’t want their children to experience. Or they might steer them into doing something that they see as more productive.

    There are various reasons they want to prevent their children from being bored. Many parents are busy with work. They’re stressed about money, child care responsibilities and managing other parts of daily life. Making sure a child is occupied with a game, a TV show or an arts and crafts project at home can help parents work uninterrupted, or make dinner, without their children complaining that they are bored.

    Parents may also feel pressure for their children to succeed, whether that means getting admitted to a selective school, or becoming a good athlete or an accomplished musician.

    Children also spend less time playing freely outside and more time participating in structured activities than they did a few decades ago.

    Easy access to screens has made it possible to avoid boredom more than ever before.

    Many parents needed to put their children in front of screens throughout the pandemic to keep them occupied during work hours. More recently, some parents have reported feeling social pressure to use screens to keep children quiet in public spaces.

    That is to say, there are various reasons why parents shy away from their kids being bored. But before striving to eliminate boredom completely, it’s important to know the benefits of boredom.

    A young girl with dark hair lays on her stomach on a couch with her arms and legs splayed out.
    Even very young children could benefit from experiencing boredom in short spurts. Oscar Wong/Moment via Getty Images

    Benefits of boredom

    Although boredom feels bad to experience in the moment, it offers real benefits for personal growth.

    Boredom is a signal that a change is needed, whether it be a change in scenery, activity or company. Psychologists have found that the experience of boredom can lead to discovering new goals and trying new activities.

    Harvard public and nonprofit leadership professor Arthur Brooks has found that boredom is necessary for reflection. Downtime leaves room to ask the big questions in life and find meaning.

    Children who are rarely bored could become adults who cannot cope with boredom. Boredom also offers a brain boost that can cultivate a child’s innate curiosity and creativity.

    Learning to manage boredom and other negative emotions is an important life skill. When children manage their own time, it can help them develop executive function, which includes the ability to set goals and make plans.

    The benefits of boredom make sense from an evolutionary perspective. Boredom is extremely common. It affects all ages, genders and cultures, and teens are especially prone to boredom. Natural selection favors traits that offer a leg up, so it is unlikely that boredom would be so prevalent if it did not deliver some advantages.

    Parents should be wary of treating boredom as a problem they must solve for their children. Psychologists have found that college students with overly involved parents suffer from more depression.

    Other research shows that young children who were given screens to help them calm down were less equipped to regulate their emotions as they got older.

    Boredom is uncomfortable

    Tolerating boredom is a skill that many children resist learning or do not have the opportunity to develop. Even many adults would rather shock themselves with electricity than experience boredom.

    It takes practice to learn how to handle boredom. Start with small doses of boredom and work up to longer stretches of unstructured time. Tips for parents include getting kids outside, suggesting a new game or recipe, or simply resting. Creating space for boredom means that there will be some stretches of time when nothing in particular is happening.

    Younger children might need ideas for what they could do when bored. Parents do not need to play with them every time they are bored, but offering suggestions is helpful. Even five minutes of boredom is a good start for the youngest children.

    Encouraging older children to solve the problem of boredom themselves is especially empowering. Let them know that boredom is a normal part of life even though it might feel unpleasant.

    It gets easier

    Children are adaptable.

    As children get used to occasional boredom, it will take them longer to become bored in the future. People find life less boring once they regularly experience boredom.

    Letting go of the obligation to keep children entertained could also help parents feel less stressed. Approximately 41% of parents in the U.S. said they “are so stressed they cannot function,” and 48% reported that “most days their stress is completely overwhelming,” according to a report from the U.S. surgeon general in 2024.

    So the next time a kid complains, “I’m bored!” don’t feel guilty or frustrated. Boredom is a healthy part of life. It prompts us to be self-directed, find new hobbies and take on new challenges.

    Let children know that a little boredom isn’t just OK – in fact, it’s good for them.

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

  • A dementia patient and his wife got their lives back thanks to a ‘coat rack-like’ robot
    Photo credit: Canva/Hello RobotStretch 4 could be one of many options for advanced senior care.

    Brenda and Brian Marquis are part of a growing senior population with mental and physical ailments. In particular, Brian has dementia from a brain injury he sustained in 2012. Brenda would help Brian remember to wash himself, eat lunch, and other tasks. On top of that, both live with other physical, cognitive, and emotional disabilities that make day-to-day living difficult. Then came “Robbie.”

    “Robbie” is the robot that helps the Marquis family with their daily routines at home. Resembling a coat rack, the robot was presented to the Marquis family after Brenda sent an email to the University of New Hampshire inquiring about robotic service dogs. Booker T. Bones, the family’s service dog, had passed away and Brenda was looking for similar support. The university saw this as an opportunity for its computer science center to experiment with “socially assistive” robots.

    “Our goal is not to replace a human caregiver but to use technology such as robots to provide complementary care,” Sajay Arthanat, a professor in UNH’s Department of Occupational Therapy told WMUR. “We know that caregivers often have to perform a lot of repetitive, mundane tasks.”

    What exactly is “Robbie”?

    “Robbie” is a Stretch 4 robot model invented by Hello Robot. While a very simple in design, the robot is able to help Brian with a number of tasks. It reminds him to eat meals at specific times, fetches items such as water bottles out of the fridge, reads the fine print of prescription medications, and more. Stretch 4 also has prompts that activate when he enters certain rooms of the home, such as the bathroom.

    “I was never into technology,” Brian Marquis said to Sentinel Colorado. “Then I realized I can’t remember to wash my face and my armpits. So, it just really kind of set me free almost.”

    Robbie hasn’t just helped Brian live more independently, but Brenda as well. She doesn’t have to be by Brian’s side 24/7. Now, she can go out and play mahjong with her friends without worrying about leaving Brian alone for several hours.

    A growing issue for older Americans

    Per the Department of Health and Human Services, the majority of older adults are projected to need long-term care and service. This could range from basic needs to extreme health cases. In addition, a 2025 report released by the Bureau of Labor Statistics found that 38.2 million people provided unpaid elder care. Around 28% of those people provided nearly four hours of unpaid elder care per day.

    The number of people who need such help is projected to grow exponentially. By 2030, the number of Americans over 65 is expected to surpass the number under 18 for the first time in U.S. history. The number of Americans over 65 years old is projected to reach 82 million, a 40% growth from 2022.

    This is, in part, why there has been such massive investment in robots and A.I. specializing in caring for elderly people. It’s not just to ensure that the elderly have the assistance they need for day-to-day tasks. Eldercare robots also boost their patient’s confidence by allowing them to live as safely and independently as they can. In addition to task-oriented robots like Stretch 4, there are also robots to assist with mobility.

    Robotics are helping improve the lives of the elderly as a new and exciting care option. With the help of medication, personal care from a human, community, and more, the growing elderly population can thrive through their golden years. For more eldercare resources, visit the National Institute on Aging.

    Whether through use of a robot or not, finding solutions to aid and care for our older populations ultimately benefits society as a whole.

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