Video·1 min read·June 2026

Heat and Cold: The 5th Pillar to Live Long and Well

Thermal stress—both heat and cold—as the fifth pillar of longevity alongside nutrition, movement, sleep, and social connection.

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Heat and Cold: The 5th Pillar to Live Long and Well: Full Transcript

0:00

hi I'm Dr Bobby deoy and welcome to live long and well a podcast we will talk about what you can do to live as long as possible and with as much energy and vigor that you wish together we will explore what practical and evidence supported steps you can take come join me on this very important journey and I hope that you feel empowered along the way I'm a physician Iron Man triathlete

2:00

exposure to heat and exposure to cold and these include things like Improvement in your mood less likelihood of a heart attack and living longer so really important benefits now doing this may only take 15 or 20 minutes in a sauna or 3 to 5 minutes in a cold environment a few times a week and you don't need fancy equipment or expensive stuff certainly not for the cold cold shower will work or a few bags of ice

4:00

thing now sweat back are in many other cultures like ancient Rome and Greece and Native Americans so heat has been around for a long time as a way of affecting how we feel cold perhaps goes back even longer maybe 3500 BC on Papyrus documents now the ancient Greeks used it for relaxation and socialization and probably not much different than the hot baths that they might have done there but cold has a medicinal history

6:00

about 100 140 ° it's new and certainly they from a marketing standpoint will say it's better than the conventional ones but I'm not necessarily convinced that there's studies to show that's the case so either one is wonderful cold exposure is pretty straightforward you either have a high ice bath or maybe a cold plunged tank or even just taking a cold shower especially in the winter and

8:00

60-year - old uh frame and none had hypertension at Baseline and so they followed these people up for 25 years and what they found was for people who were using saunas four to seven times a week which is quite often they had a 50% lower likelihood of developing high blood pressure so a profound impact on one of the most powerful risk factors for a heart attack or a stroke or death so if you can do

10:00

of people and then you randomly say you're going to do a sauna regularly and you're going to do nothing or not do a sauna and then you follow these people the problem is that to see a benefit might take years and maybe decades and that's a randomized trial that's likely not to be done it's just too difficult and to ask people to do something several times a week for the rest of their life um likely compliance would be

12:00

sudden cardiac death and if you did it four to seven times a week it was 5% or half of the risk of sudden cardiac death in in those people who are regular Sona users versus those who are not well the other way to look at those response is how long you spent in the sauna on average each time and so they compare people that were in there for less than 10 minutes those that were there for 10 to 19 minutes and those that were there

14:00

and in this study they took a a group of people who were depressed primarily they were complaining about fatigue and loss of appetite and so they randomized them some people did sauna and some people didn't and their routine was a 15minute sauna 5 days a week for a month and even in that short period of time of a month the people who used sauna had much better mood and they just overall felt better on a number of measures compared

16:00

not SAA users or only one Sona use there were substantial improvements in inflammatory uh production so again not necessarily convincing convincing evidence but another one of the theories as to why sauna on a regular basis might reduce the risk of of these various issues well most of the studies I've talked about although not exclusively um came from Finland and why fin Finland well we think of Sweden and fin Finland

18:00

you need to be aware of so I hope people are excited motivated that in fact sauna may be something to bring into your life now how about exposure to cold I have spoken to countless people about the benefits of heat and cold and they say Dr Bobby I think I could do some saunas I just have to find one or join a gym that has one but this a cold exposure I just don't think I can do it it's cold it's uncomfortable I don't like the cold

20:00

so and what they found was that at 24 hours after significant exercise people felt much more able to go back and exercise and some of the blood tests that measure muscle breakdown were also better so that's the second benefit of cold exposure the third is and I notice this every time I use it because it's a pretty immediate effect it improves your mood so there's a really interesting study done done in one of the Nordic

22:00

their studies of doing that simple approach and what they found is and they did a a study where they put people in cold water not nearly as cold as what I was just talking about and they had them in there for about an hour it was probably about 60 ° and they measured uh a number of different hormones and chemicals in the blood and what they found was that the dopamine level which is sort of your happy hormone went up

24:00

Cosmetic fat that we worry about in our belly or our our legs and such is is um one type of fat called subcutaneous fat there's also the fat that's around our organs like our liver and our muscle and that causes inflammation and heart disease and that's called visceral fat but there's a third fat called Brown fat now brown fat might sound bad but it's actually really good we don't have a whole lot of it but it's helping us to

26:00

or so uh after I do it so what do I do not that this is a science-based assessment but you know I've read all the evidence and have tried it out so maybe it's helpful to learn what I do well when I do a sauna I feel afterwards quite relaxed in contrast when I do a cold plunge it wakes me up I feel rejuvenated awake and that happy up State can last for hours now some people say oh it's great

28:00

famous n of one study so what's our n of one study assess something at basine what is it you want to improve do you think maybe it's your sleep your energy level your general mood maybe your blood pressure and find a way to measure this at Baseline now clearly if it's blood pressure you have a home blood pressure monitor you can see what your blood pressure is typically if it's sleep many people have an aura ring or an

30:00

as many people as I can convince have started to do it now the time commitment fortunately is modest if you're just going to do a cold shower at the end a couple of minutes that's very easy and can fit into your day if it's a sauna yeah it's a little bit more time and then you got to figure out where there's a sauna you can use and I would love it if people did the N of one study and and see what you think if it makes a

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well. com that's Dr drbob livelong andw well. com

Transcript auto-generated by YouTube. Verbatim — duplicates intentionally preserved.

Key Insights

Hormesis (this topic in depth) through temperature exposure activates longevity pathways

Sauna (discussed further here) + cold plunge combination produces synergistic benefits

Cardiovascular adaptation from repeated thermal stress

Integrated into lifestyle, not isolated intervention

"The body adapts to what you consistently demand of it—controlled stress builds resilience when applied deliberately."

Wim's Wise Words

A second take, from someone who's lived it.

🧊 Wim's Wise Words

#6: Exposure To Heat And Cold: The 5th Pillar to Live Long and Well

The Fifth Pillar

Dr. Bobby Deoy's framing here is useful precisely because it's so grounded. Not breathless promises, not biohacking theater—just a physician and Ironman triathlete making a quiet, evidence-based case that thermal stress belongs alongside nutrition, movement, sleep, and social connection as a foundational pillar of longevity. That framing matters. It removes thermal protocols from the fringe and places them in the center of a practical health conversation.

The core claim is straightforward: deliberate exposure to heat and cold, done consistently and without expensive equipment, produces measurable benefits—reduced heart attack risk, improved mood, longer life. Fifteen to twenty minutes in a sauna. Three to five minutes in a cold environment. A few times a week. That's the protocol. Accessible to almost everyone.

What the Research Actually Shows

The Finnish study he references is one I keep returning to. Twenty-five years of follow-up. People using saunas four to seven times a week had a 50% lower likelihood of developing high blood pressure. Not a modest reduction—half the risk, on one of the most powerful cardiovascular risk factors we know. That's not noise. That's a signal that deserves to be taken seriously.

It aligns precisely with what Rhonda Patrick has documented, and what the knowledge base reflects across multiple papers: repeated thermal stress is cardiovascular training. Your heart rate climbs, plasma volume expands, vasculature dilates and adapts. You're conditioning your circulatory system every time you sit in that hot room.

The cold side of the equation connects to something equally compelling. A 2015 study in the knowledge base found that cold acclimation significantly improved insulin sensitivity—markers of metabolic health shifting measurably after sustained cold exposure. Better glucose regulation, reduced inflammation, a more metabolically active body. Dr. Susanna Soberg's work echoes this: the discomfort of cold exposure is part of the mechanism, not something to minimize.

"Thermal stress isn't an intervention you add to a healthy life. It's a dimension of the healthy life itself—woven into the ritual, not bolted on as an afterthought."

Where the Conversation Gets Interesting

Deoy is appropriately skeptical about infrared saunas versus conventional ones. He's honest that the marketing has outrun the evidence. I appreciate that restraint. The Finnish data—the strongest longevity data we have—was collected in traditional high-heat saunas, not infrared. Either may work. But the burden of proof sits with the newer technology, not the other way around.

The Practical Recommendation

Treat thermal exposure like you treat exercise—consistent, dosed, and scheduled. Don't wait until you feel like it. Build the ritual. Two to four sauna sessions per week, 15-20 minutes, followed by a brief cold plunge or cold shower. The contrast amplifies the cardiovascular adaptation and adds a cortisol reset that compounds over time.

The Surprising Connection

Deoy places this in historical context—heat rituals in ancient Rome, Greece, Native American cultures, cold documented on Egyptian papyrus going back to 3500 BC. That lineage is worth pausing on. These weren't primitive practices replaced by better medicine. They were sophisticated stress adaptation protocols that modern science is now explaining. We didn't discover hormesis. We just finally gave it a name.