Quick answer
- Long-running Finnish studies link frequent sauna use with lower rates of fatal heart events, dementia and stroke.
- Those studies are observational and used traditional saunas, so they show strong links, not proof.
- Trials point the same way: adding a 15-minute sauna after exercise improved fitness and blood pressure more than exercise alone.
- The research pattern is frequency, so build a habit you'll actually keep.
In this article · 8 sections
If you've been reading about sauna and brain health, or saunas and longevity, you've probably met the Finnish studies. They're some of the most interesting research in wellness, and they're worth understanding properly: what they found, what they can't prove, and what they suggest about building a sauna habit.
The Finnish heart study
The best-known sauna research comes from Kuopio, Finland, where researchers followed 2,315 middle-aged men for a median of nearly 21 years. Compared with men who used a sauna once a week, those who went four to seven times a week had a 63% lower risk of sudden cardiac death after adjusting for other risk factors, along with lower risks of fatal heart disease and death from any cause. Sessions longer than 19 minutes were also linked to fewer fatal heart events (JAMA Internal Medicine, 2015).
Sauna and brain health
The same men were tracked for memory diseases. Those who used a sauna four to seven times a week had about a 66% lower risk of dementia and a 65% lower risk of Alzheimer's disease than once-a-week users (Age and Ageing, 2017).
A second Finnish study widened the lens to 13,994 men and women followed for 39 years. People who used a sauna 9 to 12 times a month had a lower risk of dementia than those who rarely or never did, with the strongest link in the first 20 years (Preventive Medicine Reports, 2020). And in 1,628 men and women aged 53 to 74, four to seven sessions a week was linked to a roughly 60% lower risk of stroke (Neurology, 2018).
What these studies can and can't tell you
These are observational studies. They follow people's habits and health over many years, which makes them good at spotting strong patterns and unable to prove that the sauna caused them. Frequent sauna users may also move more, stress less or have more free time, and no study can adjust for everything. The researchers themselves call for more work on why the links exist, and most of this research used traditional Finnish saunas, which run hotter than infrared.
So we'll be plain: no one can promise that a sauna will prevent dementia, stroke or heart disease. What the research shows is a strong, consistent link worth paying attention to, attached to a habit that's easy to enjoy.
What experiments add
Trials are smaller, but they point the same way:
- In 102 adults with at least one heart risk factor, a single 30-minute sauna lowered blood pressure and arterial stiffness right afterward (Journal of Human Hypertension, 2018).
- In a randomized trial of 47 inactive adults, adding a 15-minute sauna after exercise for eight weeks improved fitness, systolic blood pressure and total cholesterol more than exercise alone (American Journal of Physiology, 2022).
- For infrared heat specifically, a small 2001 study found two weeks of daily 140°F infrared sauna sessions improved blood vessel function in 25 men with heart risk factors (Journal of the American College of Cardiology, 2001).
A systematic review of 40 studies of regular dry sauna use found that most reported health benefits, while noting that only 13 were randomized trials and most were small (Evidence-Based Complementary and Alternative Medicine, 2018). For the deep dive, the team behind the Finnish studies summarized the field in Mayo Clinic Proceedings in 2018.
Why the habit matters most
Look at the Finnish findings again and one pattern stands out: the links were with how often people went. Not one heroic session, but regular ones. That's good news, because what makes a habit stick is simple.
- Time away from screens. Twenty minutes in the heat is twenty minutes of not answering anything. Phones don't love the heat anyway, so leave yours with your bag.
- A ritual with a start and a finish. Book it, show up, heat, cold, shower, done. The sameness is the point.
- A friend. Talk through the first round, go quiet for the second. Plans with another person are harder to cancel.
- Comfort over intensity. A session you look forward to every week is easier to keep than a punishing one you dread.
How often is right for you? Our guide on how often to sauna and cold plunge walks through it, and infrared vs traditional saunas explains the difference in heat.
How to build a sauna habit that lasts
- Attach it to something you already do. After Saturday's run, before Wednesday's workday, Sunday evening.
- Pick the studio on your route. San Diego or Temecula, whichever you pass most.
- Start shorter than you think. A 25-minute session is a complete session.
- Book ahead, so the decision is already made.
- Make it easy to repeat. Coming weekly or more? A pack or a membership saves you deciding every time.
Questions worth asking your doctor
If heart or brain health is part of why you're starting, bring a few questions to your next checkup:
- Is regular sauna use a good fit with my heart, my blood pressure and any conditions I have?
- Do any of my medications change how I handle heat or cold?
- How hot, how long and how often makes sense for me?
- Is a cold plunge a good idea for me, and for how long?
A note on heat and safety
Heat puts real demands on your body, which is part of why a sauna feels like something. If you have a heart condition, high or low blood pressure, are pregnant, or take medication that changes how you handle heat, check with your doctor before you start. Drink water, skip alcohol, and get out whenever you feel dizzy or unwell.
Questions people ask.
Is a sauna good for your brain?
Research links frequent sauna use with brain health. Finnish men who used a sauna four to seven times a week had about a 66% lower risk of dementia than once-a-week users. It's an observational finding: a strong link, not proof.
Does sauna use help you live longer?
In a Finnish study that followed 2,315 men for about 20 years, frequent sauna users had a lower risk of death from any cause. It's a strong association from traditional saunas, not a promise.
Does the research apply to infrared saunas?
Not automatically. The long-term studies used traditional Finnish saunas, which run hotter. Infrared research is smaller and earlier, though a small study found infrared sessions improved blood vessel function.
How often did people in the studies use a sauna?
The strongest links in the Finnish research were at four to seven sessions a week, compared with once. Any regular habit you can keep is a good place to start.
Can I bring a friend into the sauna?
Yes. Your suite is private, and you can add a guest when you book. The infrared sauna has room for three.
Sources
- Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Internal Medicine, 2015.
- 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.
- Knekt P, et al. Does sauna bathing protect against dementia? Preventive Medicine Reports, 2020.
- Kunutsor SK, et al. Sauna bathing reduces the risk of stroke in Finnish men and women: a prospective cohort study. Neurology, 2018.
- Laukkanen T, et al. Acute effects of sauna bathing on cardiovascular function. Journal of Human Hypertension, 2018.
- Lee E, et al. Effects of regular sauna bathing in conjunction with exercise on cardiovascular function: a multi-arm, randomized controlled trial. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, 2022.
- Imamura M, et al. Repeated thermal therapy improves impaired vascular endothelial function in patients with coronary risk factors. Journal of the American College of Cardiology, 2001.
- Hussain J, Cohen M. Clinical effects of regular dry sauna bathing: a systematic review. Evidence-Based Complementary and Alternative Medicine, 2018.
- Laukkanen JA, Laukkanen T, Kunutsor SK. Cardiovascular and other health benefits of sauna bathing: a review of the evidence. Mayo Clinic Proceedings, 2018.
