Sauna bathing has gone from a Finnish tradition to one of the most popular recovery tools in gyms, spas and home wellness rooms. Some of the claims you see online are well supported, some are stretched, and some are made up. Here is what the published research says, and what it doesn't.
Key takeaways
- Large Finnish studies link frequent sauna use with lower rates of cardiovascular death and dementia. These are observational studies: they show an association, not proof that sauna causes the benefit.
- A 2018 systematic review found regular dry sauna use is generally well tolerated by healthy adults and may support cardiovascular and other health markers.
- A small study in runners found post-exercise sauna sessions were followed by better endurance performance after three weeks.
- Sauna is not right for everyone. Talk to a doctor first, especially with heart conditions, low blood pressure or pregnancy.
The Finnish heart study everyone quotes
The most-cited sauna paper is a 2015 study in JAMA Internal Medicine led by Tanjaniina Laukkanen. Researchers followed 2,315 middle-aged Finnish men for about 20 years. Men who used a sauna 4 to 7 times a week had a lower rate of fatal cardiovascular events and all-cause death than men who went once a week [1].
That is a striking result, but it needs context. The study was observational, which means the researchers watched what people already did rather than assigning them to sauna or no sauna. People who sauna more often may differ in other ways (income, free time, overall health). The study also included only men in Finland, where sauna culture is very different from the U.S. It is fair to say frequent sauna use is associated with better outcomes. It is not fair to say a sauna will add years to your life.
Sauna and brain health
The same Finnish group later reported that men who used a sauna 4 to 7 times a week had a lower risk of dementia and Alzheimer's disease than once-a-week users [2]. Again, this is an association from an observational group. It's an interesting signal and a reason for more research, not a treatment claim.
What a systematic review found
A 2018 systematic review by Joy Hussain and Marc Cohen pulled together clinical studies on regular dry sauna bathing. They concluded that sauna use appears safe for most healthy people and may have benefits for conditions including high blood pressure, heart failure and some musculoskeletal pain, while noting that many of the studies were small and more rigorous trials are needed [3].
Sauna after training
For athletes, one frequently cited study comes from New Zealand. Six competitive male runners added about 30 minutes of sauna after training, several times a week, for three weeks. Their time to exhaustion in a running test improved compared with a control period, and the researchers suggested an increase in blood volume as a possible reason [4]. Six runners is a very small group, so treat this as promising rather than settled.
Infrared vs. traditional: does the research apply to both?
Most of the large studies, including the Finnish ones, were done with traditional Finnish saunas at high air temperatures. Infrared saunas heat you at lower air temperatures and have less long-term research behind them. That doesn't mean infrared doesn't work. It means you should be careful about borrowing results from one type and applying them to the other. Our sauna buying guide compares the two in more detail.
What this means for gyms and studios
Sauna is one of the easiest recovery amenities for members to understand. It's familiar, it's social, and it pairs naturally with cold plunge for contrast sessions. For a studio, a sauna can be the anchor of a recovery zone that gives members a reason to stay after class and come back on rest days. See our guide to building a recovery room.
Safety basics
- Hydrate before and after. Avoid alcohol before or during a session.
- Start short (10 to 15 minutes) and build up.
- Get out if you feel dizzy, nauseated or unwell.
- Check with your doctor first if you have heart disease, low or high blood pressure, are pregnant, or take medications that affect heat tolerance.
References
- Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Internal Medicine. 2015;175(4):542-548. doi:10.1001/jamainternmed.2014.8187
- Laukkanen T, Kunutsor S, Kauhanen J, Laukkanen JA. Sauna bathing is inversely associated with dementia and Alzheimer's disease in middle-aged Finnish men. Age and Ageing. 2017;46(2):245-249. Find on PubMed
- Hussain J, Cohen M. Clinical effects of regular dry sauna bathing: a systematic review. Evidence-Based Complementary and Alternative Medicine. 2018;2018:1857413. Find on PubMed
- Scoon GSM, Hopkins WG, Mayhew S, Cotter JD. Effect of post-exercise sauna bathing on the endurance performance of competitive male runners. Journal of Science and Medicine in Sport. 2007;10(4):259-262. Find on PubMed
The information on this site is for general education and is not medical advice. Talk with your doctor before starting heat, cold, light, pressure, float, PEMF or vibration therapy, especially if you are pregnant or have a medical condition. We may earn a commission when you buy through our links. Learn more.