Does sauna use lower heart disease risk?
Short answer
Possibly, but not proven in trials.
Finnish men who used saunas more often had fewer heart deaths and less new high blood pressure, but that is a link. Small, short trials give mixed blood pressure results.
This page says what the research shows. It does not say whether you should use a sauna.
Where the evidence stands
Each dot is one on-topic paper. Steps near the top answer the question more directly. Select a dot to see the study.
↑ Stronger evidence
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Trials in people: heart disease, blood pressure and death
Trials that measured heart disease, blood pressure and death directly.
3 -
Trials in people: other measures
Trials that measured other health or performance measures.
2 -
Trials in people: lab tests or safety
Trials that measured lab tests, side effects or safety.
5 -
Population studies
Studies that followed or surveyed groups of people. They show links, not causes.
4 -
Blood levels and genes
Studies that link blood levels or genes to health.
0None among the papers we read.
↓ Weaker evidence
- Points to benefit
- Mixed
- No difference
- No direction
- Points to harm
Not on the ladder: 5 reviews of many studies (shown below), 2 opinion or narrative papers. Counts are papers, not people. Some studies appear in more than one paper.
See every studyWhat we found
- Among 2315 Finnish men tracked 20.7 years, those taking saunas 4 to 7 times weekly, versus once, had under half the risk of sudden heart death (hazard ratio 0.37). Laukkanen 2015
- In the same Finnish study, 1,621 men without high blood pressure who took saunas 4 to 7 times weekly had about half the risk of developing it (hazard ratio 0.54). Zaccardi 2017
- In a trial of 47 inactive adults, adding a 15-minute sauna after exercise for 8 weeks lowered systolic (top-number) blood pressure by 8.0 mmHg more than exercise alone. Lee 2022
- In a trial in forty-one adults with narrowed heart arteries, 8 weeks of Finnish sauna 4 times a week did not change blood pressure versus no sauna. Debray 2023
What the research says
Finnish cohort links frequent sauna to fewer deaths
One long-running study of men in eastern Finland supplied all the population data. Men who took saunas more often had fewer sudden heart deaths, fatal heart disease and deaths from any cause, and longer sessions also tracked with lower heart death risk.
Two later papers from the same cohort, with 2575 men, found 3 to 7 sessions a week, versus 2 or fewer, linked to lower death from any cause (hazard ratio 0.86). These show links, not causes.
Studies: Laukkanen 2015, Zaccardi 2017, Kunutsor 2022, Kunutsor 2024
Blood pressure: reviews and trials disagree
Two pooled reviews found lower blood pressure. One found systolic pressure fell 5.26 mmHg after 2 to 4 weeks of sauna. Another, of heat therapy in general, found a fall of 3.94 mmHg; its abstract does not say how many studies used saunas.
Other results disagree. A heart failure review found no clear effect of infrared sauna on blood pressure. Among trials, sauna after exercise lowered systolic pressure 8.0 mmHg more than exercise alone in 47 adults, but 8 weeks of Finnish sauna did not change it in forty-one heart patients.
Studies: Li 2020, Pizzey 2021, Källström 2018, Lee 2022, Debray 2023
Heart failure: short sauna courses improved heart measures
Most trials tested Waon therapy, a 60°C far-infrared dry sauna, in heart failure patients for 10 days to 4 weeks. In 188 patients, 2 weeks of sauna raised the heart's pumping share and lowered BNP, a blood marker of heart strain; controls did not change.
In the multicenter WAON-CHF trial (76 sauna, 73 control patients), the main measure, BNP, did not clearly change, though symptom class, 6-minute walk and heart size improved. A review pooling seven studies found BNP and pumping improved over 2 to 4 weeks.
Studies: Miyata 2008, Tei 2016, Källström 2018, Fujita 2011, Kuwahata 2011
One small study tracked heart failure events
In 129 patients with severe heart failure, those given Waon sauna at least twice a week had heart failure events or heart death in 31.3%, versus 68.7% of matched patients on usual care, over 60 months.
Patients were matched, not randomly assigned, so the groups may have differed in other ways. A heat therapy review reported the same 31.3% figure among 65 patients, so it may not be separate evidence.
Studies: Kihara 2009, Ye 2020
What reviews of many studies found
Reviews pool or sum up earlier studies. They are not on the ladder, because they repeat studies already counted there.
Pooled review (meta-analysis) · Källström 2018
Searched for controlled studies of sauna in heart failure; nine qualified, all infrared sauna, and seven were pooled. Over 2 to 4 weeks, BNP and heart size fell and pumping improved; blood pressure did not clearly change.
Pooled review (meta-analysis) · Li 2020
Summarized sixteen sauna articles. Right after a sauna, systolic pressure fell 5.55 mmHg; after 2 to 4 weeks it was 5.26 mmHg lower and heart pumping (LVEF) rose 3.27%. Authors concluded sauna helps heart function, most in weak hearts.
Pooled review (meta-analysis) · Pizzey 2021
Pooled 15 heat therapy studies (type not named) in healthy and sick people. Heat lowered systolic pressure by 3.94 mmHg and diastolic by 3.88 mmHg; resting heart rate did not change. Certainty was rated moderate.
Pooled review (meta-analysis) · Ye 2020
Pooled heat therapy studies in heart failure: sixteen studies on 506 patients showed pumping (LVEF) up 4.4%, and blood pressure fell in 431 patients of 15 studies. The authors called mild heat an effective add-on therapy.
How the research grew
The papers we read span 1983 to 2026. 2 of the 21 on-topic papers came out in 2024 to 2026. The earliest trial in people here is from 1983.
- 1980–84
- 2005–09
- 2010–14
- 2015–19
- 2020–24
- 2025–26
Each dot is one on-topic paper, colored by what it found. Rings mark key papers:
- 1983. Early trial: sauna series lowered resting blood pressure. Winterfeld 1983
- 2008. Randomized study of 188 heart failure patients. Miyata 2008
- 2009. Five-year follow-up: fewer heart failure events with Waon. Kihara 2009
- 2015. Finnish cohort links frequent sauna to fewer heart deaths. Laukkanen 2015
- 2023. Finnish sauna trial in heart patients: no vascular gains. Debray 2023
Who was studied
Who took part, and how many. The largest trial here had 188 people; the largest population study had 2,575.
- Trials in people
- Population, blood and gene studies
- 1,621 people · Zaccardi 2017
middle-aged men from Eastern Finland aged 42-60 without high blood pressure at the start - People in the study, log scale1101001,00010,000
- Points to benefit
- Mixed
- No difference
- No direction
- Points to harm
Bars use a log scale: each step is ten times more people. Reviews, animal studies and papers with no count in the abstract are not shown.
Who funds this research
None of the 10 relevant trial papers shows a company stake. Only one, the sauna-plus-exercise trial, declares no conflicts; the other nine have no disclosure in PubMed. This did not change the confidence.
- No disclosure in PubMed 9
- No stake declared 1
- Tei 2016No disclosure in PubMed
- Ichiki 2017No disclosure in PubMed
- Fujita 2011No disclosure in PubMed
- Kuwahata 2011No disclosure in PubMed
- Kominami 2020No disclosure in PubMed
- Kihara 2009No disclosure in PubMed
- Debray 2023No disclosure in PubMed
- Winterfeld 1983No disclosure in PubMed
- Miyata 2008No disclosure in PubMed
- Lee 2022No stake declared
Funding rule. A stake is always shown. Confidence is lowered only when every supporting study comes from a party with a stake. "No disclosure in PubMed" means the PubMed record has no conflict-of-interest statement. It does not mean there is no conflict.
All 21 on-topic papers
Each paper shows what it tested, what it found, and who has a stake. Every paper also has its own page that explains how much it counts and how it fits. See every study as a list.
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Randomized trial · measured the question itselfLee et al., 2022American journal of physiology. Regulatory, integrative and comparative physiology · PubMed
Effects of regular sauna bathing in conjunction with exercise on cardiovascular function: a multi-arm, randomized controlled trial.
47 people · inactive adults aged about 49 with at least one heart disease risk factor
Tested8 weeks of exercise plus a 15-minute sauna after each session, vs exercise alone, vs no change in routine
Exercise plus sauna gave lower systolic blood pressure (-8.0 mmHg; 95% CI, -14.6 to -1.4 mmHg) and better fitness (+2.7 mL/kg/min) than exercise alone. Exercise alone did not change blood pressure vs control.
Points to benefitNo stake declaredAbstract onlyNo competing interests declared.
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Trial, not randomized · measured the question itselfKihara et al., 2009Journal of cardiology · PubMed
Waon therapy improves the prognosis of patients with chronic heart failure.
129 people · people with severe chronic heart failure
TestedFar infrared dry sauna at 60 degrees C for 15 min, daily for 5 days then at least twice a week, vs usual heart failure care, followed 5 years
Heart failure events or heart death happened in 68.7% of the control group but only 31.3% of the sauna group (P<0.01) at 60 months. 12 control and 8 sauna patients died.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Trial, not randomized · measured the question itselfWinterfeld et al., 1983Zeitschrift fur die gesamte innere Medizin und ihre Grenzgebiete · PubMed
[Effect of sauna and walking series on blood pressure, peripheral microcirculation and performance behavior in essential hypertension].
people with mild to moderate high blood pressure already taking propranolol
TestedSauna baths over several weeks, vs a running series
Both sauna baths and running lowered blood pressure at rest and improved blood flow in the muscles. Under heavier exercise load, blood pressure was not changed by either method.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Finnish sauna bathing and vascular health of adults with coronary artery disease: a randomized controlled trial.
41 people · adults aged about 62 with stable coronary artery disease
TestedFinnish sauna 4 times a week, 20-30 min each, at 79°C, for 8 weeks, vs keeping usual lifestyle
Artery widening (FMD) did not differ: control 0.07% vs sauna 0.15% (interaction P = 0.909). Systolic (P = 0.951) and diastolic (P = 0.292) blood pressure did not differ between groups.
No differenceNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Beneficial effects of Waon therapy on patients with chronic heart failure: results of a prospective multicenter study.
188 people · people with chronic heart failure on standard treatment
TestedFar infrared dry sauna at 60 degrees C for 15 min daily for 2 weeks, then rest, vs standard treatment alone
Ejection fraction rose from 31.6+/-10.4% to 34.6+/-10.6% (p<0.0001) with sauna but not in controls. BNP fell from 542+/-508 pg/ml to 394+/-410 pg/ml (p<0.001); not in controls.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Randomized trial · lab tests or safetyKominami et al., 2020International journal of hyperthermia · PubMed
Cardiovascular reactions for whole-body thermal therapy with a hot pack and Waon therapy.
19 people · healthy young men
TestedOne session of dry sauna (Waon) and one of whole-body hot packs, each followed by rest, compared in the same men
Blood pressure did not change significantly after either therapy. Brachial artery widened equally (HPTT: 3.70 ± 0.57 ⇒ 4.05 ± 0.59 mm; WT: 3.63 ± 0.63 ⇒ 3.93 ± 0.61 mm).
No differenceNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Neurohumoral Modulation During Waon Therapy in Chronic Heart Failure - Subanalysis of Waon-CHF Study.
150 people · people with chronic heart failure
TestedWaon therapy (dry far infrared sauna) vs usual care, with blood hormone levels checked
Heart-related blood hormones BNP, Aldo and CNP were not statistically different between sauna and control groups, although clinical measures improved. Some subgroups on certain heart drugs did better in the sauna group.
No differenceNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Waon Therapy for Managing Chronic Heart Failure - Results From a Multicenter Prospective Randomized WAON-CHF Study.
149 people · hospitalized people with advanced heart failure
TestedFar infrared dry sauna at 60℃ for 15 min once a day for 10 days, then 30 min bed rest, vs usual care
The main measure, BNP (a heart strain blood marker), did not reach statistical significance. Heart failure class, 6-min walk distance and heart size ratio improved only in the sauna group. No serious adverse events.
MixedNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Effect of Waon therapy on oxidative stress in chronic heart failure.
40 people · people with chronic heart failure, plus heart-disease hamsters
TestedDaily far infrared dry sauna at 60°C for 4 weeks vs usual care alone
BNP fell from 402±221 to 225±137pg/ml (P<0.001) in the sauna group and did not change in controls. Hydroperoxide, a stress marker, fell from 422±116 to 327±88U.CARR. Hamster tests found less heart stress too.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Improvement of autonomic nervous activity by Waon therapy in patients with chronic heart failure.
54 people · people with chronic heart failure on usual treatment
TestedWaon therapy (dry sauna) plus usual treatment for 4 weeks, vs usual treatment alone
Among 27 sauna patients, cardiac output and ejection fraction rose after 4 weeks but did not change in 27 control patients. Heart rate variability moved toward calmer nerve activity only in the sauna group.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Sauna bathing and mortality risk: unraveling the interaction with systolic blood pressure in a cohort of Finnish men.
2,575 people · Finnish men aged 42 to 61
TestedSauna use (low: 2 or fewer sessions a week vs high: 3-7 a week) and blood pressure level, followed a median 27.8 years
Low vs high sauna use was linked to 16% higher death risk (HR 1.16, 95% CI 1.02-1.31). High blood pressure with low sauna use: HR 1.47 (1.24-1.74). High blood pressure with high sauna use: HR 1.24 (0.98-1.57).
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Inflammation, sauna bathing, and all-cause mortality in middle-aged and older Finnish men: a cohort study.
2,575 people · Finnish men aged 42 to 61
TestedSauna use (low: 2 or fewer sessions a week vs high: 3-7 a week) and a blood marker of inflammation, followed a median 27.8 years
High vs low sauna use: HR 0.86 (0.76-0.97) for all-cause death. High inflammation with low sauna use: 1.28 (1.12-1.47). High inflammation with high sauna use: 1.06 (0.81-1.40), no clear link.
Points to benefitNo stake declaredAbstract onlyNo competing interests declared.
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Sauna Bathing and Incident Hypertension: A Prospective Cohort Study.
1,621 people · middle-aged men from Eastern Finland aged 42-60 without high blood pressure at the start
TestedHow often men took saunas (1, 2-3, or 4-7 times a week), followed for a median 24.7 years
Compared with 1 sauna a week, the hazard ratio for new high blood pressure was 0.76 (95% confidence interval: 0.57-1.02) for 2 to 3 and 0.54 (0.32-0.91) for 4 to 7 sessions. After more adjustment: 0.83 (0.59-1.18) and 0.53 (0.28-0.98).
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Association between sauna bathing and fatal cardiovascular and all-cause mortality events.
2,315 people · middle-aged men from Eastern Finland aged 42-60
TestedHow often men took saunas (1, 2-3, or 4-7 times a week) and how long, followed for about 20.7 years
Compared with 1 sauna a week, the hazard ratio of sudden cardiac death was 0.78 (95% CI, 0.57-1.07) for 2 to 3 and 0.37 (95% CI, 0.18-0.75) for 4 to 7 sessions per week. Similar links for heart disease and all-cause death.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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The effect of heat therapy on blood pressure and peripheral vascular function: A systematic review and meta-analysis.
15 studies · healthy people and people with health conditions
TestedHeat therapy for 30-90 minutes, over 10-36 sessions, vs control
Heat therapy lowered systolic blood pressure (MD: -3.94 mmHg, 95% CI: -7.22, -0.67) and diastolic (MD: -3.88 mmHg, 95% CI: -6.13, -1.63). Resting heart rate did not change (MD: -1.25 beats/min).
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Acute and short-term efficacy of sauna treatment on cardiovascular function: A meta-analysis.
16 studies · people in sauna studies, including people with weak heart function
TestedSauna right after a session (0-30 min) and sauna treatment for 2 to 4 weeks, vs before or no sauna
Right after a sauna, systolic blood pressure fell 5.55 mmHg and diastolic 6.50 mmHg. After 2 to 4 weeks, systolic fell 5.26 mmHg and diastolic 4.14 mmHg. Pumping strength (LVEF) rose 3.27%.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Can heat therapy help patients with heart failure?
people with heart failure
TestedThermal therapy that raises body temperature by up to 1.4°C, vs no therapy
Sixteen studies on 506 patients showed LVEF up 4.4%. Blood pressure fell in 431 patients of 15 studies. Among 65 patients, thermal therapy reduced cardiac death and rehospitalization by 31.3%.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed; funders include a heart institute and public research councils.
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Effects of sauna bath on heart failure: A systematic review and meta-analysis.
9 studies · people with heart failure
TestedInfrared sauna at 60°C for 15 minutes, 5 times a week for 2 to 4 weeks, vs no sauna
Infrared sauna was linked to lower BNP (a heart strain blood marker), smaller heart size ratio and better ejection fraction. There was no effect on systolic or diastolic blood pressure. Only infrared saunas qualified.
MixedNo stake declaredAbstract onlyNo competing interests declared.
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Effect of Waon Therapy in Individuals With Heart Failure: A Systematic Review.
people with heart failure
TestedWaon therapy (a gentle dry-heat sauna treatment)
No abstract in PubMed.
No directionNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Opinion or narrative reviewNagai et al., 2026International journal of environmental research and public health · PubMed
Effects of Bathtub Bathing and Sauna Practices on Cardiovascular and Systemic Health: A Narrative Review.
adults in studies of hot bathtub bathing or sauna
TestedReview of studies on habitual bathtub bathing (17 studies) and sauna use (28 studies)
Sauna bathing, studied mostly in Finnish cohorts, was linked to lower heart disease and all-cause death, and better inflammation and artery-lining markers. Bathtub evidence was limited to observational studies of markers. The authors call for studies with clear clinical endpoints.
No weight on the ladderNo stake declaredAbstract onlyNo competing interests declared.
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Sauna use as a lifestyle practice to extend healthspan.
general adult populations (review of sauna research)
TestedOverview of sauna use at 45 °C to 100 °C and its effects on the body
The authors describe large Finnish cohort studies linking sauna use to lower illness and death risk, in a dose-dependent way. No new data or numbers are given in the abstract.
No weight on the ladderNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
20 papers we read and set aside as off topic
- Ferreira et al., 2023. Cardiovascular autonomic modulation during passive heating protocols: a systematic review. (systematic review)
- Mao et al., 2023. Associations between extreme temperature exposure and hypertensive disorders in pregnancy: a systematic review and meta-analysis. (pooled review (meta-analysis))
- Goodall et al., 2020. A Narrative Review of the Use of Neuromuscular Electrical Stimulation in Individuals With Diabetic Foot Ulceration. (systematic review)
- Harwood et al., 2021. A systematic review of the role of heat therapy for patients with intermittent claudication due to peripheral artery disease. (systematic review)
- Sebők et al., 2021. Heat therapy shows benefit in patients with type 2 diabetes mellitus: a systematic review and meta-analysis. (pooled review (meta-analysis))
- Lee et al., 2025. Regular postexercise sauna bathing does not improve heart rate variability: A multi-arm randomized controlled trial. (randomized trial)
- Okamoto et al., 2021. Local Passive Heat for the Treatment of Hypertension in Autonomic Failure. (randomized trial)
- Greaney et al., 2015. Impairments in central cardiovascular function contribute to attenuated reflex vasodilation in aged skin. (randomized trial)
- Akerman et al., 2019. Heat therapy vs. supervised exercise therapy for peripheral arterial disease: a 12-wk randomized, controlled trial. (randomized trial)
- Brunt et al., 2016. Passive heat therapy improves endothelial function, arterial stiffness and blood pressure in sedentary humans. (trial, not randomized)
- Chavez et al., 2026. Acute effects of passive heat exposure on vascular function and exercise capacity in patients with chronic kidney disease. (randomized trial)
- Ro et al., 2025. Feasibility of unsupervised, home-based leg heat therapy in older adults: a pilot, sham-controlled trial. (randomized trial)
- Beever, 2010. The effects of repeated thermal therapy on quality of life in patients with type II diabetes mellitus. (trial, not randomized)
- Youngstedt et al., 1993. Does body temperature mediate anxiolytic effects of acute exercise? (randomized trial)
- Kaiser et al., 2025. No effect of either heat therapy or aerobic exercise training on blood pressure in adults with untreated hypertension: a randomized clinical trial. (randomized trial)
- Hartard et al., 2025. Influence of heat therapy and/or vibration on nonspecific back pain: A prospective, open, randomized, controlled, parallel-group clinical study. (randomized trial)
- Périard et al., 2011. Central and peripheral fatigue during passive and exercise-induced hyperthermia. (randomized trial)
- Brunelle et al., 2024. Evidence-based recommendations regarding risk reduction practices for people at risk of or with breast cancer-related lymphedema: consensus from an expert panel. (other)
- Laukkanen et al., 2017. Sauna bathing is inversely associated with dementia and Alzheimer's disease in middle-aged Finnish men. (population study: followed a group)
- Kunutsor et al., 2018. Sauna bathing reduces the risk of stroke in Finnish men and women: A prospective cohort study. (population study: followed a group)
Words on this page
- Hazard ratio (HR)
- Compares how often something happened in two groups over time. 1 means no difference. 0.80 means 20% lower risk; 1.20 means 20% higher.
- 95% CI (confidence interval)
- The range where the true result likely lies. If the range includes no effect (1 for ratios, 0 for differences), the result is not clear.
- p-value (p =)
- How likely a result this large would be by chance if there were no real effect. Below 0.05 is usually called a clear result.
- Pooled review (meta-analysis)
- A study that combines the results of many earlier studies to get one overall answer.
- Cohort study
- A study that follows a large group of people over years. It shows links, not causes.
- BNP
- A blood marker of heart strain. Higher means more strain.
- LVEF
- The share of blood the heart pumps out with each beat.
- mmHg
- The unit for blood pressure.
- Systolic pressure
- The top number in a blood pressure reading.
- Diastolic pressure
- The bottom number in a blood pressure reading.
- Marker
- A lab or scan result that stands in for a health outcome. A better marker does not always mean better health.
How the short answer is set
Fixed rules turn the studies into the short answer, so the same studies always give the same answer. The rules start from GRADE, a standard system for rating evidence, in plain language.
| Confidence | What it means |
|---|---|
| High | We are confident the answer is right. |
| Moderate | The answer is probably right, but it could change. |
| Low (this page) | The answer may well change. |
| Very low | Any answer is very uncertain. |
| Not tested in people | Only cell or animal studies exist. |
Why low here
- Trials were small, 19 to 188 people, and lasted days to weeks.
- Blood pressure results disagree across trials and pooled reviews.
- Death links come from one cohort of Finnish men: links, not causes.
- More frequent sauna use tracked with lower risk, a dose-response pattern.
Hard limit used. No randomized trial in these papers counted heart attacks or deaths, so the death findings show links, not proof that sauna prevents them.
How this page was made
Label
- Search
- PubMed, Nov 14, 2026. Searches written by Claude Opus 5.5; papers ranked by PubMed
- First read of all 41 papers
- Claude Sonnet
- Independent second read
- Claude Haiku
- Disagreements settled by
- Claude Opus 5.5
- Page text written by
- Claude Opus 5.5
- Charts
- Drawn by code from the study records
- Source check by a person
- Not yet. Required before search engines may list this page.
- Expert review
- No
- Papers read in full
- 0 of 41; all from PubMed abstracts
- Method
- v0.2, created Nov 14, 2026
Search. We ran four PubMed searches for sauna bathing and heart disease, blood pressure and death: pooled and systematic reviews since 2012 (10 of 12), trials in people (22 of 73), population studies (10 of 21). The first number is how many papers we read; the second is how many PubMed found. We took the ones PubMed ranks as most relevant. See the full PubMed search. Of the 41 papers read, 21 were on topic.
Limits. Digestery reads at most about 60 papers per question, so large fields are sampled, not covered in full. Abstracts can leave out key details, such as side effects and funding.
Review queue
These items wait for a person. Search engines are asked not to list the page until the first one is done.
- OpenThe short answer is new. It waits for a source check by a person.
- OpenOne Finnish Kuopio cohort: Laukkanen 2015, Zaccardi 2017, Kunutsor 2022, Kunutsor 2024 (plus off-topic Laukkanen 2017, Kunutsor 2018). Counted once as evidence.
- OpenKunutsor 2022 and Kunutsor 2024 share 2575 men and 1618 deaths; HR 0.86 and 1.16 look like the same comparison reversed.
- OpenWAON-CHF trial: Ichiki 2017 is a subanalysis of Tei 2016 (UMIN000006705). Counted once.
- OpenLee 2025 (heart rate variability, set off-topic) appears to be the same trial as Lee 2022; analyzed numbers differ (38 vs 47).
- OpenYe 2020 reports 31.3% fewer heart deaths and rehospitalizations in 65 patients; this may be Kihara 2009's data. Check before counting separately.
- OpenKihara 2009, Kuwahata 2011 and Fujita 2011 cite the authors' own earlier Waon work; check for shared patients and device ties.
- OpenTei 2016 abstract contradicts itself on BNP (improved vs not significant); check the full text.
- OpenKaiser 2025 (null blood pressure trial) set off-topic because heat type is not in the abstract; include it if it used sauna.
- OpenPizzey 2021 and Ye 2020 pool heat therapy generally; abstracts do not say how many studies used sauna.
- OpenRocha Conceição 2018, a Waon heart failure systematic review letter, has no abstract; marked relevant but unused.
- OpenKunutsor 2018 (stroke, Kuopio cohort) set off-topic because stroke is not heart disease; reconsider if stroke should count.
- OpenKihara 2009 is a matched, non-randomized comparison; Miyata 2008 calls itself case-control but says patients were randomized.
- OpenNine of 10 relevant trial papers have no conflict-of-interest statement in PubMed.
Page history
| Date | Change | Reason |
|---|---|---|
| Nov 14, 2026 | Page created from 41 papers. | First version of the page. |
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