Traditional Sauna: The Format the Research Was Actually Done In
When people cite "the sauna research," they are almost always citing studies done in traditional saunas. Not infrared. This article explains what a traditional sauna is, what those studies looked at, and why the type of sauna matters when you read the results.
What a traditional sauna is
A traditional sauna uses an electric heater with a bed of rocks on top. The heater warms the air in the room, and the hot air warms you. Pouring water on the rocks releases a burst of steam and raises the humidity for a short time. In Finnish this is called löyly.
Air temperature in a traditional sauna usually runs 150 to 195°F (65 to 90°C), higher than an infrared cabin, because the whole point is to heat the air. A steam room is a related format that runs cooler with much higher humidity.
When comparing traditional saunas, the numbers that differ are the heater power in kilowatts, the voltage (120V or 240V), the bench layout and how many people it seats, and the wood.
The Finnish cohort research
The most cited body of sauna research comes from a long running study in eastern Finland. Researchers enrolled about 2,300 middle aged men, recorded how often each used a sauna, and followed them for roughly two decades, tracking health outcomes over that time.
- Laukkanen T, et al. JAMA Internal Medicine. 2015;175(4):542 to 548. PMID 25705824.
- Laukkanen JA, et al. Age and Ageing. 2017;46(2):245 to 249. PMID 27932366.
- Laukkanen JA, et al. Mayo Clinic Proceedings. 2018;93(8):1111 to 1121. PMID 30077204.
In that group, more frequent sauna use was associated with lower rates of several heart and brain related outcomes over the follow up period. People using a sauna 4 to 7 times a week showed larger differences than people using one once a week. The associations held after the authors adjusted for common risk factors like age, blood pressure, smoking, and cholesterol.
Why "the format that was studied" is a real distinction
These studies were done in traditional Finnish saunas. That means high air temperature, the option of added steam, and session lengths and habits typical of Finnish sauna culture.
Infrared saunas heat you differently, at a lower air temperature, usually drier. They are a newer technology, and the long term research specific to infrared is still being built. Where infrared studies exist, they tend to be smaller and shorter, and results for the two formats are usually reported separately.
So if your interest is specifically in reproducing the conditions of the cardiovascular research above, that points toward a traditional sauna. If tolerability, a lower install burden, or a drier heat matter more to you, infrared is worth considering, with the understanding that its evidence base is less mature. A separate article compares the two in detail.
How to read an observational study
The Finnish research is observational. It shows that a habit and an outcome tend to occur together. It does not, on its own, prove the sauna use caused the difference.
- People who use a sauna several times a week may differ from people who never do in ways that are hard to fully measure, such as overall lifestyle or access to healthcare.
- The participants were middle aged Finnish men. The size of an association can be different in women, other age groups, or other countries.
- The authors adjusted for many known risk factors, which strengthens the finding, but adjustment is never perfect.
The specific effect sizes and statistical details are laid out in the protocol guide, with the study design attached, rather than quoted here as bare numbers.
Heat and sleep
One shorter term effect tied to heat is about body temperature. Warming up and then cooling down is associated with falling asleep faster, through the same drop in core temperature the body uses at night (Harding EC, Franks NP, Wisden W. Frontiers in Neuroscience. 2019;13:336. PMID 31105512). This is why an evening sauna session, finished with enough time to cool before bed, is a common placement. It is a link to faster sleep onset, not a treatment for insomnia.
What the research does not establish
- It does not show that a sauna treats, cures, or prevents any disease or medical condition.
- The strongest data is observational, and it was collected in traditional saunas, not infrared.
- A sauna is a general wellness device, not medical equipment, and not a substitute for medical care.
Where to start
Heat is one of three inputs. Whether you add it first, or after cold and light, depends on your current sleep, recovery, activity level, schedule, and how much heat and cold exposure you already do.
Find My Protocol matches those five answers to a starting point and a week by week plan. It takes about two minutes and does not require a purchase.
References
- Laukkanen T, et al. JAMA Internal Medicine. 2015;175(4):542 to 548. PMID 25705824. pubmed.ncbi.nlm.nih.gov/25705824
- Laukkanen JA, et al. Age and Ageing. 2017;46(2):245 to 249. PMID 27932366. pubmed.ncbi.nlm.nih.gov/27932366
- Laukkanen JA, et al. Mayo Clinic Proceedings. 2018;93(8):1111 to 1121. PMID 30077204. pubmed.ncbi.nlm.nih.gov/30077204
- Harding EC, Franks NP, Wisden W. Frontiers in Neuroscience. 2019;13:336. PMID 31105512. pubmed.ncbi.nlm.nih.gov/31105512
For the specific effect sizes from these studies, and the full protocol details, see the protocol guide.
The products sold by Peak Regenerate are not medical devices and are not intended to diagnose, treat, cure, or prevent any disease or medical condition. This article is for educational and informational purposes only. Talk to your physician before starting any heat, cold, or light exposure routine, especially if you have a heart condition, are pregnant, or take prescription medication. Individual results vary. Peak Regenerate does not provide medical services through this platform.
