Hot rods? We love fast planes and cars, and why not, hot is good. But hot air can make takeoffs and rate of climb challenging, and everyone abhors those who spew hot air about any number of subjects. Aviators are cool characters and don’t get hot under the collar. But what if I told you getting hot under the collar might actually be good for you?
While a Visiting Professor at the world-famous Karolinska Institute in Stockholm, I was introduced to the idea of deliberately sitting in a hot, wet wooden box, sweating profusely, and repeating several times a week. The Nordic countries, and others, swear by the health benefits of saunas, and when you examine the science, something remarkable emerges; regular sauna use appears to confer significant cardiovascular, neurological, and longevity benefits.
Which raises an intriguing question: Does living in a hot, steamy climate like Louisiana, Florida, or beyond offer the same benefits? Or is there something special about the sauna itself?
Let’s turn up the heat and examine the evidence.
Much of what we know about sauna health benefits comes from Finland, where sauna use is not an indulgence but a way of life. The landmark Kuopio Ischemic Heart Disease study followed middle-aged men over two decades and produced striking findings.
Compared to men who used a sauna once weekly, those indulging four to seven times per week had:
Add reductions in blood pressure, decreased inflammation, improved sleep, and better mood, and the humble sauna begins to look less like a luxury and more like a public health intervention.
These are not marginal gains; they are clearly transformative. However, these figures represent hazard ratios; in other words, relative risk reductions should be interpreted cautiously. Additionally, this is observational data, potentially meaning association rather than proof of causation. As Tyler Vigen humorously illustrated in Spurious Correlations, ice cream sales correlate with shark attacks, not because one causes the other, but because both rise in summer.
How does this happen? The key lies in how the body responds to heat stress. Within minutes of entering a sauna, heart rate rises (often above 100 beats per minute), blood vessels open (dialate), cardiac output increases, and surprise, surprise, sweating commences. Sound familiar? These changes resemble those that occur with exercise, which also leads to improved vascular function, lower blood pressure, reduced inflammation, and enhanced autonomic nervous system control of heart and vessels. This all points to a more efficient and durable cardiovascular system.
Additionally, heat exposure increases levels of brain-derived neurotrophic factor (BDNF), a protein associated with the nervous system’s ability to react, and cognitive resilience, which might partially explain the reduced dementia risk. Other proteins are produced that condition the body to deal with stress and are associated with the lifespan of cells and the person who owns them!
However, not all heat is equal. The Finnish data are clear: frequency, duration, and intensity matter and one should aim for 80–90°C (176–194°F) for 15–20 minutes, 3–7 times/week, short bursts of high heat followed by cooling.
So, does living in a hot, sticky region provide similar benefits? Sadly, not quite, as the exposure in muggy Missouri, boiling Brownsville, or clammy Kailua is prolonged, moderate (30–35°C / 86–95°F), and without structured cooling cycles. The intermittent heat of a sauna is a controlled stressor, a process we call hormesis. Another example of hormesis is intense, regular but intermittent exercise which strengthens muscle. In other words what doesn’t kill us makes us stronger.
And by contrast, chronic heat exposure can cause persistent dehydration, which is often unrecognized, damages many organs, strains heart and vessels, and provokes heat fatigue. It doesn’t train the body, it taxes it. And we all know what we think about taxes. In hot climates people stay indoors, use air-conditioning, and limit exercise during peak heat; as Nöel Coward sang in 1931, “Only mad dogs and Englishmen go out in the midday sun.” Sauna use, by contrast, is intentional and structured.
Additionally, when using a sauna, one tends to drink plenty of fluids before and after, limit duration, and know when to stop. Of course, this is one reason the research may be flawed; the sort of people who use saunas also tend to treat their bodies kindly, be mindful about things like hydration, and affirmatively choose a healthy lifestyle.
Before Minnesota and Alaska readers start celebrating, living in a warm environment may improve circulation and encourage outdoor activities, although the hardy and adventurous are never constrained by temperature.
With some medications, particularly for high blood pressure, sauna use can be associated with increased risk of low blood pressure and passing out, so consider medical advice before using a sauna.
If considering incorporating sauna use into your routine, bear in mind it is not a substitute for regular exercise or a good diet, but here are some evidence-based guidelines: hydrate well and avoid alcohol before and after, limit initial sessions to 10–15 minutes, cool down slowly—ice plunge pools are not a great idea—and if dizzy, leave, drink fluids, and rest.
From an aviation perspective, going from sauna to Cessna is not wise. Without rest and rehydration, fatigue, headache, dizziness, and even fainting might ensue. Additionally, although there is the aforementioned long-term cognitive benefit, in the short term, even minor core temperature elevation can negatively impact attention, decision-making, and reaction time.
The Kuopio study is respected in the medical community as a large, long-term, well-conducted observational study, but it is not definitive. Because it is observational rather than a randomized trial, it cannot prove that sauna use directly causes these benefits—frequent users may simply be healthier overall, more active, or differ in other lifestyle factors. In addition, the study population was largely middle-aged Finnish men, which limits how broadly the findings can be applied. Major academic centers therefore regard the evidence as promising and biologically plausible, but not yet strong enough to be prescriptive, meaning we cannot yet say “you should do this.” Cleared for the option if you will.
Hot stuff used to apply to a snazzy new plane or a particularly gifted aviator. If we can cut through the overheated hype like a hot knife through butter, wouldn’t it be chill if the data confirms that hot-tuning your body was a cool prescription?
Stay cool—and Fly Well.
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