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Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...

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August 29 2018

What Can Heat Do For Your Health?

By Mark Sisson
52 Comments

A few months ago, I explored the benefits and applications of cold therapy. Today, I’m going to talk about the benefits and applications of heat therapy—one of the most ubiquitous and ancestral therapies in the history of humankind. You name a culture and—as long as they didn’t live in perpetual tropical heat—they probably had some form of heat therapy. Native Americans had the sweat lodge, those of Central America the temazcal. The Romans had the thermae, which they picked up and refined from the Greeks. Other famous traditions include Finnish saunas, Russian banyas, Turkish hammams, Japanese sentó (or the natural spring-fed onsen), and the Korean jjimjilbang. People really like the heat.

Right off the bat, that’s one major benefit to heat therapy compared to cold: It’s an easy sell. “You can luxuriate in a sauna for half an hour or lower your naked body, genitals first, into a bathtub filled with ice water. Your choice.” People are far more likely to sit in the hot room for 20 minutes than they are to sit in an ice bath for 3 minutes or even take a cold shower. Short-term heat exposure is generally regarded as pleasant. Cold exposure is generally regarded as torture. If heat therapy offers legit health benefits, this is a major point in its favor. So, does it?

Oh, yes.

In a recent review of the available observational studies, controlled trials, and interventions, researchers found evidence that sauna usage has an impressive array of beneficial effects on health and wellness:

  • Increased lifespan and decreased early mortality.
  • Reduced cardiovascular disease.
  • Lowered blood pressure.
  • Improved cognitive function and reduced the risk of neurodegenerative disease.
  • Improved arthritis symptoms.

What’s going on here? How could sitting in a hot room do so many good things?

Stress, in a word. One of the coolest things about us is that encountering, facing down, and then growing resistance to one type of stress tends to make us better at dealing with stress from other sources. A 30-minute sauna session at 174 ºF/80 ºC raises body temperature by almost 1 degree C, spikes your flight-or-flight hormones, raises cortisol, and triggers a powerful hormetic response by the rest of your body. That’s a stressor. After such a session, subjects report feeling “calm” and “pleasant.” This isn’t a surprise. Intense exercise also raises cortisol in the short term. And like regular exercise, longer term sauna usage (daily for four weeks in one study) actually reduces stress hormones.  It’s a classic hormetic response, where acute doses of the stressor increase oxidative stress enough to provoke a compensatory adaptation by the organism.

What does this sauna-induced hormetic stress do for us?

Benefits of Heat Therapy

It reduces oxidative stress. Short term, it increases stress (that’s why we see the transient spike in cortisol and other stress hormones). Long term, it reduces oxidative stress. Long-term sauna use has an inverse association with levels of C-reactive protein (CRP), a “catch-all” biomarker for oxidative stress and inflammation. The more often you use the sauna, the lower your CRP.

It may reduce mortality. The more frequently a person visits the sauna, the lower his risk of premature death from heart attack and all causes. There is a dose-response relationship happening here, which has me leaning toward “causal.” Those using the sauna two to three times a week had a 23% lower risk of fatal heart attack compared to men who used it just once a week. Men who used the sauna four to seven times a week had a 48% reduced risk of fatal heart attack compared to once-a-weekers. The more frequently men used the sauna, the greater the protection (for other causes of mortality, too).

It improves vascular function. A single bout of sauna (or exercise, for that matter) reduces vascular resistance—the amount your blood vessels “resist” blood flow—in hypertensive patients for up to two hours.

It’s good against type 2 diabetes. Sauna use has been shown to improve almost every marker related to type 2 diabetes, including insulin sensitivity, fasting blood sugar, glycated hemoglobin, and body fat levels.

It can improve depression scores. Patients with depression who underwent heat therapy saw improvements in their Hamilton Depression Rating.

If you’re an athlete, or exercise at all, you should try the sauna. Training magnifies the benefits of the sauna.

Finally, pairing exercise and heat therapy together is a boon for cardiovascular health. For instance, people who frequent the sauna and the gym have a drastically lower risk of heart attack death than people who do either alone. That combo also reduces 24-hour blood pressure in hypertensive patients and confers special protection against all-cause mortality above and beyond either variable alone.

Post-Workout Benefits

Post-workout sauna sessions improve endurance performance in runners: For three weeks, endurance runners sat in 89° C (+/- 2° C) humid saunas for 31 minutes following training sessions. This amounted to an average of 12.7 sauna sessions per runner. Relative to control (no sauna), sauna use increased time to exhaustion by 32%, plasma cell volume by 7.1%, and red cell volume by 3.2% (both plasma cell and red cell volume are markers of increased endurance performance).

Post-workout sauna use increases plasma volume in male cyclists: Following training sessions, cyclists sat in 87° C, 11% humidity saunas for 30 minutes. Just four sessions were sufficient to expand plasma volume. This is important because increasing plasma volume improves heat dissipation, thermoregulation, heart rate, and cardiac stroke volume during exercise.

Post-workout sauna—either dry or steam—can also alleviate muscle fatigue.

How About Pre-Workout?

The effects are more mixed. In one study, pre-workout sauna reduced strength endurance and 1 rep max leg press, had no effect on 1 rep max bench press, and improved maximum power (vertical leap). Another study found that in female athletes but not in males, maximum power decreases after sauna use. It’s possible that these performance disturbances are caused by dehydration rather than the heat itself, so make sure you rehydrate if you’re planning on training after a sauna session.

If you want to apply heat pre-workout without overdoing it, I’ve always liked a nice hot bath to help limber up, mobilize my joints, and clear out any stiffness for the coming workout session.

Oh, and It Can Help You Detox

I was going to write the full word “detoxification,” but I figured I’d write “detox” just to trigger the hardcore skeptics reading this…. Heat exposure can augment your natural detoxification capacities by at least two mechanisms.

First, exposure to extreme heat increases something called heat shock proteins, or HSPs. HSPs are responsible for many of the benefits of heat therapy, including enacting beneficial hormetic effects on our detoxification capacity. They trigger compensatory adaptations and activate antioxidant defenses in the blood of healthy volunteers. They even increase regeneration of the body’s main detoxifying organ—the liver—after it’s been damaged.

Second, contrary to popular belief, sweating can aid detoxification. Sweat itself contains bioaccumulated toxins, including BPA—even when it doesn’t show up in the blood or urine. Sweat also contains certain phthalate compounds and their metabolites, none of which we want. Sweat also contains arsenic and lead in people exposed to high levels of the metals. Sweating may even improve the function of another important detoxification organ—the kidney—by restoring nitrogen excretion in people with kidney disease. In one study, police officers with chronic illnesses caused by exposure to high levels of meth lab chemicals experienced major improvements after sauna therapy.

What If You Don’t Have Access To a Sauna?

There are other options.

Steam rooms work. Only problem with them is it’s difficult to remain in one long enough to trigger the necessary stress response. Saunas, with their dry heat, are easier to stick with. Steam rooms feel different enough that I wonder if there’s something unique about them. Not enough evidence to go on, unfortunately. Perhaps I can revisit this later.

Jacuzzis and hot baths work. A recent paper found that taking regular hot baths at home improved insulin sensitivity and increased nitric oxide synthase activity about as much as working out. Another found that, compared to showering, bathing improved mood, perceived stress, blood flow, and accumulation of metabolic waste products.

You could probably sit in a black car on a hot day with the windows rolled up and get an effect.

Just get hot, as hot as you can stand. Then stay a little longer. (As always, be sure to talk to your doctor. Certain conditions and scenarios, like pregnancy, require extra caution with saunas or other forms of heat therapy.)

Have you used the sauna? Are you a regular attendee? Or do you use other means of heat therapy? I’m curious to hear your experiences, tips, and stories below.

References:

Laukkanen JA, Laukkanen T, Kunutsor SK. Cardiovascular and Other Health Benefits of Sauna Bathing: A Review of the Evidence. Mayo Clin Proc. 2018;93(8):1111-1121.

Leppäluoto J. Human thermoregulation in sauna. Ann Clin Res. 1988;20(4):240-3.

Sutkowy P, Wo?niak A, Rajewski P. Single whole-body cryostimulation procedure versus single dry sauna bath: comparison of oxidative impact on healthy male volunteers. Biomed Res Int. 2015;2015:406353.

Laukkanen JA, Laukkanen T. Sauna bathing and systemic inflammation. Eur J Epidemiol. 2018;33(3):351-353.

Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Intern Med. 2015;175(4):542-8.

Krause M, Ludwig MS, Heck TG, Takahashi HK. Heat shock proteins and heat therapy for type 2 diabetes: pros and cons. Curr Opin Clin Nutr Metab Care. 2015;18(4):374-80.

Laukkanen JA, Laukkanen T, Khan H, Babar M, Kunutsor SK. Combined Effect of Sauna Bathing and Cardiorespiratory Fitness on the Risk of Sudden Cardiac Deaths in Caucasian Men: A Long-term Prospective Cohort Study. Prog Cardiovasc Dis. 2018;60(6):635-641.

Kunutsor SK, Khan H, Laukkanen T, Laukkanen JA. Joint associations of sauna bathing and cardiorespiratory fitness on cardiovascular and all-cause mortality risk: a long-term prospective cohort study. Ann Med. 2018;50(2):139-146.

Gayda M, Paillard F, Sosner P, et al. Effects of sauna alone and postexercise sauna baths on blood pressure and hemodynamic variables in patients with untreated hypertension. J Clin Hypertens (Greenwich). 2012;14(8):553-60.

Hedley AM, Climstein M, Hansen R. The effects of acute heat exposure on muscular strength, muscular endurance, and muscular power in the euhydrated athlete. J Strength Cond Res. 2002;16(3):353-8.

Gutiérrez A, Mesa JL, Ruiz JR, Chirosa LJ, Castillo MJ. Sauna-induced rapid weight loss decreases explosive power in women but not in men. Int J Sports Med. 2003;24(7):518-22.

Genuis SJ, Birkholz D, Rodushkin I, Beesoon S. Blood, urine, and sweat (BUS) study: monitoring and elimination of bioaccumulated toxic elements. Arch Environ Contam Toxicol. 2011;61(2):344-57.

Genuis SJ, Beesoon S, Birkholz D, Lobo RA. Human excretion of bisphenol A: blood, urine, and sweat (BUS) study. J Environ Public Health. 2012;2012:185731.

Khodarev VN, Zhemchuzhnova NL, Olempieva EV, Kuz’menko NV. [The influence of general infrared sauna on the antioxidant systems in the blood of volunteers]. Vopr Kurortol Fizioter Lech Fiz Kult. 2013;(5):10-3.

Shi Q, Dong Z, Wei H. The involvement of heat shock proteins in murine liver regeneration. Cell Mol Immunol. 2007;4(1):53-7.

Mccarty MF, Barroso-aranda J, Contreras F. Regular thermal therapy may promote insulin sensitivity while boosting expression of endothelial nitric oxide synthase–effects comparable to those of exercise training. Med Hypotheses. 2009;73(1):103-5.

Goto Y, Hayasaka S, Kurihara S, Nakamura Y. Physical and Mental Effects of Bathing: A Randomized Intervention Study. Evid Based Complement Alternat Med. 2018;2018:9521086.

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52 thoughts on “What Can Heat Do For Your Health?”

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  1. I use a far infra red Matt. The generic name is bio mat. It makes me sweat, it’s like a poor man’s sauna.

  2. Interesting that this appeared in my inbox today. Recently, I had been reading about some of the positive impacts of heat therapy so this morning I spent some time in the Sauna in the gym after my workout. I’m really glad to hear it from you Mark! I’m going to continue with it and see how it goes. Thanks!

  3. I believe it. I think I remember hearing about heat therapy being used in Europe by people dealing with cancer.

  4. Have there been studies that show how heat/cold work together? For example, 20 minutes in the sauna to raise the body temp and then jump into a pool or snowbank. We used to do this when my parents had a sauna. My brother used to swan dive off the deck into the snowbank he’d shoveled just for the occasion 8=)

    And what about the lashing with willow branches that I’ve heard of? I’ve never tried it myself. Seems like too much effort while trying to relax.

    1. The lashing in my experience was in a Russian sauna. They had two buckets inside the sauna which were filled with water and had branches in them. I’m not sure which kind they were. But we were to lash each other with them once we were warm. Indeed it took effort and had a curious feel, from the thick, wet leaves slapping our skin to feeling completely self-conscious about doing something seemingly so strange! But we did feel rejuvenated once we were done. Seems the slapping kind of electrified the body. Definitely something to experience.

      1. Birch twigs including the leaves are traditionally used in Europe

  5. A really hot topic …

    I have access to a Finnish sauna and I don’t use it very often, I’m smacking myself upside the head right now and making a committment to use it at least twice a week!

  6. any thoughts on using a FAR Tnfraed sauna vs the old fashioned finnish style dry or steam version?

    1. https://www.marksdailyapple.com/are-infrared-saunas-beneficial/

      This might answer some of your questions. I bought a near infra-red sauna several months ago and loved it during winter. Hard to comment on health benefits from such a short usage time so far. Summer has been harder to convince myself that I want to be even hotter than regular daily temps provide but I’ll be heading back to it soon!

  7. Over the last few years I have been going to the sauna after my workout a few days a week. I can’t stay in longer than 15-20 mins or so because it just get too hot!! We also have a infrared sauna at my parents that I try and hit occasionally. I have been telling them they need to use it more and more and now I can send this article to them so they can read the benefits for themselves.

    Thanks Mark!!:)

  8. I read and enjoy your publications Mark, thanks. I have been using the sauna since my pre-teens, so that’s 50 plus years. The last 3 and a half have been in the infra red, combined with daily workouts and ketogenic adaptations. Pre workout sauna, for me at least, results in a little less maximum workout strength, improved flexibility and similar or greater endurance. That’s at 6 or 7 workouts per week. In addition, there has been a noticeable improvement in lung function, and almost a complete elimination of the need for prescription drugs for type 2 diabetes and blood pressure. I heartily endorse the sauna to improve your health.

  9. Lots of Finnish references but the Fins are not one of the Blue Zone populations. Of the 5 BZ populations, the Okinawans may use a sauna/hot springs – not sure about the the other 4 though.

  10. If cold exposure helps me live longer than I am going to die young because I loathe cold. Only mentally deranged masochists can possibly like cold bats. In my 20s I deliberately moved to where it never snowed or saw natural ice. I don’t even like cold drinks…

    1. However I love saunas… at least three times a week, at last 20 minutes each.

  11. I have to use my car as my sauna. I park in the sun for that purpose, however, most of the year it’s cloudy so no too hot.
    I work in an office that others think it “too hot”, complaining about how horrible it is – 73 to 75 degrees – good grief!!! What did people do before air conditioning? Certainly NOT DIE of heat exposure when it is 73 to 75 degrees!!!
    Now here’s proof of what I’ve been saying all these years, heat is better for your health!

  12. I use an infrared sauna about once per week for 60 minutes. I would do it more if I owned one (on my list). I feel amazing after. Recently I’ve started doing a session immediately after getting a lymphatic drainage (after a bout with Bell’s). It was as if water was pouring through my pores. Same effect when I did a Vishesh Swedna session. I’ve also used the light therapy sauna (can’t recall the proper name). Great article. A sauna is definitely worth the splurge to me. Thanks

    1. I feel like Mark alludes to this without directly mentioning it in those terms. Heat exposure stimulates your sympathetic nervous system short term (the acute stressor part), with increased parasympathetic activity post-sauna as well as long-term.

  13. I don’t have access to a sauna, but I do try to do Bikram yoga 2-3 times per week. By the end of a 60-minute express practice you feel like you want to die because you’ve sweated so much. But about 30-45 minutes after you finish you feel completely energized. And I have found nothing else that helps keep aches and pains away like a regular Bikram practice 🙂

    1. Someone mentioned reading a study about how hot yoga was bad for the organs. Does sauna also have this effect—or do you have to be engaging in strenuous activity in the heat for that to occur? I will try to find the actual study to see if the methods/findings are anything to listen to.

  14. Mark- I personally enjoy a daily session in my communities Spa & Fintess Center’s steam room. Have tried our dry heat sauna but do not feel the benefit I receive from steam. However, most of not all the benefits you cite from your ‘Heat’ article I feel I am enjoying very much.

  15. Great article Mark!

    The sauna is very important to me for two primary reasons. Firstly, the sauna became a staple part of my health regimen when I recently needed to go through a complete detox to prepare for getting my mercury amalgam fillings removed from my teeth (July 2018), and then afterwards, since the half-life of mercury detox is rather long (actual time depends on the type of mercury, how toxic, etc). I followed all the recommendations (err, all except one, see under) and I ended up in Bangkok to have the actual dental work done. There was no need for a sauna whilst there (plus difficult to find), but every night in my hotel I had a hot bath (as hot as I could cope with) with a cup of Epsom salts (to replace minerals), some bicarb soda and some lavender oil. The entire dental work was broken up into two 3 day blocks. This was not recommended by my Doc (he wanted me to replace each filing at 1 per month) due to the potential of having too much mercury being released into the body. But I decided to attack it aggressively; I was very detailed, and started the detox process in earnest for two months before going to Bangkok. I doubled my supplementation, which was extensive, and about a month before I hit the sauna big time. Both IR saunas and conventional saunas. I am very pleased to report that everything went perfectly, and I have not experienced any adverse detox side effects. It has now been 47 days since the dental work was completed, and I have felt incredible every day since.

    Secondly, I use saunas as part of my workout regimen (McGuff follower), and it’s very easy for me at the moment. I live in the south part of Australia. It’s winter here and yesterday the temp was 4C (39F). So I can freeze my buns off, or sit in the sauna and recover and detox. Easy choice.

    1. Hi Geoff, I’m interested in what symptoms you suffered prior to you having your mercury amalgam fillings removed? I’ve had mercury fillings since childhood (I guess for over 30 years now) curious to know if removing them would make any step improvements in how healthy I feel day to day. Can you direct me to a good source to study the pro & cons? Cheers Andy

      1. Look up the SMART protocol for removing mercury-amalgam fillings. There are plenty of studies showcasing the impact mercury can have on the body. Again, each individual is different, and some people are able to process heavy metals better, but if you are suffering from any health issues, mercury-amalgam fillings is one of the first things I’d consider.

        1. Thanks Yerasimos,
          Considering the precautions they take removing the stuff, I’m surprised we’re allowed to walk around in public with this material in our mouths! I see the EU have just banned it for kid under 15’s & adults if pregnant. Total ban proposed for 2030.
          Thanks, Andy

      2. Regarding symptoms – that is a difficult question – I learned that it is not as straight forward as what people would like. Furthermore, I didn’t even notice some of the symptoms – some were pointed out to me by my doc (functional/integrative medicine doc) who had seen them in other people with amalgams.

        Such as the color of my skin. To me it seemed “normal”, but I had been living with it for many years. He noticed that it lacked a bit of color, not quite gray-ish, but definitely older looking than what it should have been for my age. A friend saw me recently, not knowing what I had been doing, looking at me as if she was trying to figure something out. And then she asked, “Have you lost weight?…you look different.” I guess on that measure the doc was right.

        After the amalgams had been removed, my saliva no longer tasted like metal. Again, when you live with this for many years (40+) the taste of your saliva is “normal”, even if that taste is metallic. I didn’t realise it was a symptom.

        I had also experienced some unusual fatigue. At one point I thought it was chronic, but sharpened up my lifestyle and diet and become better. But with a few more years I would get tired in afternoons a lot. I no longer get tired in the afternoons. The only change was the amalgam removal.

        To wrap up symptoms…I’ve seen lists of over 50 items long…the symptoms can be, and often are, different for each person.

        My references, which include reading 4 books on the topic:

        It’s All in Your Head – Hal Huggins (1993)
        Silver Dental Fillings – The Toxic Time Bomb – Sam Ziff (1994)
        Dental Mercury Detox – Sam Ziff (1997)
        Elements of Danger – Morton Walker (2000)

        IAOMT – excellent video showing how amalgams release mercury gases – search YT “Smoking Teeth – Toxic Fillings.” This video shows how mercury vapours can be released simply by rubbing the amalgam with a pencil eraser. It is supposed to simulate chewing, or being exposed to a hot liquid, such as coffee. It takes about 90minutes for the vapours to stop. Think about that. All this time the vapours are being inhaled. (This does not include the slow release cause by internal corrosion of the amalgam itself – dissimilar metals, in contact with each other, in an electrolyte solution (saliva), creates electric currents, causing those metals to corrode. This causes a release through the dental tissue directly into the bloodstream.)

        Other online resources – you’ll find then using a simple search, as follows:

        Dr Louisa Williams website…and…
        Her book “The 5 Dental Detox Days” and
        PDF dot point brief “Mercury Amalgam Detoxification” (2016 conference paper)

        Dr Mark Hyman blog posts:
        Mercury: How To Get This Lethal Poison Out Of Your Body
        How to Rid Your Body of Heavy Metals: A 3-Step Detoxification Plan

        There’s plenty of other info out there, and I gained a stack, including pros and cons, from the above references.
        The final point to make, which was the decision point for me, was that mercury amalgam fillings are treated the same as any toxic hazard. Any qualified dentist who removes them must wear some form of respiration gear, the room needs to be positively ventilated, the patient has pure oxygen pumped into in the nostrils, rubber dams are required so that no refuse falls into the mouth, and special suction tubes are used by the assistant. Once removed, the filling is required to be placed and sealed in a container that has been approved for hazardous substances, and then that container needs to be placed and sealed in another cabinet, that is also approved. But hey, apparently it’s ok for amalgams to be in our head. Go figure.

        Hope it helps.

        1. Wow Goeff, thanks for the very comprehensive reply. Will copy to Evernote and start my research.

          Went keto/primal last year and lost 7kg, but never really felt that I’ve experienced the mental clarity benefits or shaken off a general feeling of fatigue.

          I think I’ve had at least 5 filling in my molars since I was a teenager and I’ve had gut & fatigue issues throughout my adult life.

          I’m now on a mission to see if I can resolve all these issues that I had assumed were just normal for everyone. Primal solved most of the gut issues, so I hope there may be a step improvement by removing the amalgam fillings.

          Thanks once again,
          Andy

  16. Here in Texas at the moment, all you need to do is walk outside. It is a pleasant stressor / relaxer after working in a cold lab. I try to get outside about every hour or two to get my body temperature back where it belongs.

  17. Hi Mark, I’m a 66 year old teaching (tennis) pro in Zurich Switzerland. I have a long and sordid substance abuse history having grown up in So-Cal in the 60’s and 70’s. Born in Santa Monica..You know the drill. I use the sauna a couple times a week with a big hit 4-600mg of niacin for vascular dilation (detox). It works. I still train, Train smart, Mostly strength because my students make sure I get my cardio. I’ll be on the west coast from November until March getting my dose of the pacific. I come back here to CH in spring. Let’s hit some balls, Got an in at Malibu racket club. Love your work bro, Tony

  18. I’m wondering if the benefits of saunas/steam rooms aren’t somehow connected to the cold exposure, as it is usually recommended to get into a cold water tub or take a cold shower after using sauna. Does the research on heat exposure account for that?
    And here’s an interesting fact: sauna (?a?nia) was popular in medieval Poland and the modern word for bathroom or even toilet, ?azienka, still reminds of its origins.

  19. How interesting ! Being European it’s always been an activity that was on the cards after a ‘night on the town’….followed by a dip in an icy plunge pool ! Now we live in Florida and spend a large portion of the day outside,, sweating….will this work as well I wonder ? I have osteoarthritis so actually prefer the cold now.

  20. I use my jacuzzi/spa every morning. If I do about 10-15 minutes I feel great. If I go longer it leaves me kind of beat up.

    When I use it at night I sleep like a baby.

  21. Hi has anybody used the cheap home saunas, like those sold in the big internet store for around one hundred dollars?

  22. Since I’m camping without a tent, just on a tarp on the ground with another one over it when it’s raining, I wrap up in a blanket at night because it keeps the mosquitoes off me. (Just have to listen to their bzzz whine as my lullaby, how lovely). Some of the nights are hot and after a while under the blanket I feel like I’m getting heatstroke or something and end up soaked with sweat. Sometimes I wake up for no apparent reason and figure it’s because I’ve gotten too warm. I try to tolerate the heat as much as possible for the benefits, sweating out toxins being one I prioritize because I probably get enough in my system (and again to avoid the bites.) I wouldn’t go so far as to call it therapy! Every few minutes sometimes when trying to fall asleep I have to move the blanket to get some fresh air so I don’t feel like I’m languishing and gasping in an oven. My favourite part of this is that after subjecting myself to a harsh amount of heat even a breeze I’d normally find warm becomes delightfully cooling and refreshing.
    I’ve actually woken up too warm camping in the winter in circa -20C temperatures because of the amount of insulation around me due to lots of layers of clothing and blankets. One time I got myself and I guess the air trapped under the blankets so warm that I felt like I was suffocating and that made me feel a bit panicky so I had get out from under the blankets and unzip my coats part way, which had me feeling chilly again in about a minute. That might have been the night that someone else homeless in the general area apparently froze to death. I’m always telling people that insulation is the simple secret to camping in cold weather, and then trying to stay dry.

  23. “You can luxuriate in a sauna for half an hour or lower your naked body, genitals first, into a bathtub filled with ice water. Your choice.” I literally laughed out loud at this and thus had to share with the rest of the office since they were curious. Classic. Thanks for other information as well. Very informative.

  24. So, in the name of being seasonal and living naturally, what about just getting out in the heat (and not having an air conditioner–but yet cooking a lot) in the summer and being out in the cold in the winter and keeping the house temp low? Is that enough heat/cold exposure to have beneficial effects? (Might be harder to study.) Instead of taking the time to do something extra that takes up natural resources to create, get the exposure through living. Spend half the year hot and half the year cold. (Plus the cold exposure of going to the grocery store in hardly any clothes in the summer, and the heat exposure of going to someone’s house or the local school dressed for cold in the winter.) (Of course this only works in places that have different weather in the seasons.) Isn’t that more along the lines of Grok-ness?

    1. I thought this exact thing myself. I was just thinking that surely if there’s clear benefits to heat and cold exposure, our ancestors would have gotten all of that simply by living their natural daily lives.

      I question the same thing you do – would all that be enough exposure to get the beneficial effects? I personally think that added up over time, it would. A cumulative effect sort of thing. What do you think?

  25. I particularly like a long sauna before Yoga, and see significant benefits in my practice. Sample size of one, but after 6 months of 5 saunas a week, I believe my mental faculties are improved. While I like the contrast therapy of sauna/cold plunge I do think there are benefits from allowing the body to cool naturally at least some times.

  26. Not sure if you were serious about saunaing in a hot car, but please don’t encourage this practice, as tempting as it might be. Plastic, foam rubber, carpeting, adhesives, synthetic fabrics, and other materials inside a car outgas even more when hot and can quickly build up to dangerous levels in a sealed vehicle. I always roll down all the windows with one or more door(s) open into the breeze and possibly the blowers on high set to the foot position to vent the car out before getting in on hot or sunny days. (Bonus: this also reduces the risk of shattering any overheated glass when the door bangs closed.) Some heat remains, particularly in dark seats, but this flushes out most of the air heavily laden with noxious fumes. After that I continue with open windows when possible, but if I need to close up and run AC this practice gives the machine a head start. A trick I learned from an asthmatic is to close the front windows first, when the AC starts to provide cold air, but leave the back ones open a bit longer so the fans (set for outside air not recirculated) can push the last of old hot and contaminated air out, and replace it with fresh, new, cooled air.

  27. What is the minimum amount of time one can spend in a sauna and still experience health benefits? My chance to use a sauna is very limited.

  28. Please write about deep tissue laser/cold laser therapy. It helped me miraculously.

  29. Just be careful. I had a heat stroke at 9 yeas old. It came on quickly. At least that’s how I remembered it. I was on my sisters boat when it happened. I still have problems today, over 60 years later. My husband has a problem with heat exhaustion. He turns ash grey and needs to get out of the heat, sit quietly and drink lots of water when it happens. Or take my grandfather who died of a combo of hypothermia and heart problems shoveling snow. Learn the symptoms of the various extremes of both heat and cold on your body so you can be aware of any problems before the happen so you can stay safewhile trying various temperature extremes.

  30. I regularly use a sauna after workouts at the gym, as I have seen correlation with reducing my fasting glucose levels. So much, so that we are putting a sauna in our new home.

  31. I agree heat therapy has multiple benefits , as well as the cold if your able (I can’t w/ Raynaud’s) . Combining hot springs with this seems to be the most effective . The Breitenbush Hot Springs sauna is the best example in the NW with all forms readily available to anyone staying or with a limited day use pass. I’m planning to study the effects of hot springs soaking relative to my scleroderma in 2020. Anyone interested search for The Soakers Archive and contact me for additional information.
    https://www.facebook.com/pg/TheSoakersArchive

  32. “Post-workout sauna—either dry or steam—can also alleviate muscle fatigue.”
    As an athlete, this is a big time advantage for me. Post workout recovery is almost more important than the workout itself. Our bodies are like cars. If you give a Ferrari the wrong kind of gas, it won’t run correctly. This is huge. I always thought the key to a successful post workout recovery was the miserable ice bath. Now I know, there is a warmer alternative.

  33. How long do you recommend staying in a sauna, steam room or hot tub to gain the benefits?

  34. This is great stuff. I’m curious about the ‘fever therapy’ aspect of sauna use, though. Anyone start using a sauna and notice a reduction in catching colds/flu? Flu season is ramping up where I live and it would be great to think that on top of everything else, I’m keeping myself from catching the crud too.