| Study | Design & population | Finding & comparison |
|---|---|---|
| 2018 · Strandberg TE ↗ | Cross-sectional questionnaire study Mostly home-living survivors of Helsinki Businessmen Study Participants: 524. Self-reported sauna habits | Current sauna use was associated with better selected quality-of-life domains, but mobility and health could influence continued use. Comparison: Current users versus nonusers Cross-sectional design |
| 2024 · Engström Å ↗ | cross-sectional population survey general population respondents Participants: 971. habitual sauna bathing | Sauna users reported better health measures but also differed in age, sex and lifestyle. Comparison: sauna bathers versus non-bathers Cross-sectional self-report; selection and confounding; no causal timing. |
| 2020 · Choi HS ↗ | Uncontrolled before-after intervention Adults with BMI at least 25 Participants: 38. Dry sauna · Twice daily for 4 consecutive days | Quality-of-life scores improved, but body composition, BMI, blood pressure and heart rate did not change significantly. Comparison: Baseline versus two days after last session No untreated comparator described |
Original publication: Sauna bathing, health, and quality of life among octogenarian men: the Helsinki Businessmen Study.
What did this older-men study compare?
The study compared current sauna habits and health-related quality of life among men who responded at very old ages. It asked about an existing practice, not a new exposure assigned by investigators. The favorable finding therefore concerns an association between current use and selected questionnaire domains.
This is different from asking whether beginning sauna improves later life. A person still using a familiar practice may differ from someone who has stopped for health or mobility reasons. The paper is useful because it makes that selection question concrete. Its result should not be presented as a randomized older-adult intervention merely because the participants were elderly and the outcome was personally important.
Who was available to participate?
The survey included 524 mostly home-living survivors of the Helsinki Businessmen Study, aged 80–95 years. It was a male survivor sample, rather than a representative group of every older adult, care setting or level of functional ability. The opportunity to survive, remain available and respond is part of the design context.
Those features limit transfer even before the sauna comparison is considered. The study cannot retrospectively include people who died earlier, did not respond or could no longer participate. A favorable domain score among the available respondents does not establish an effect for everyone outside the sample. The enrollment frame needs to stay beside any claim about healthy aging or later-life wellbeing.
Does nonuser mean someone who never used sauna?
Not necessarily. The abstract describes decreased or discontinued habits, and many people not currently attending had used sauna earlier. The current-user comparison therefore should not be relabeled as lifelong sauna exposure versus lifelong nonuse. These categories describe present participation within a familiar cultural practice.
That distinction affects interpretation. Stopping can be related to changing health or mobility, while continued use can identify people still able and willing to participate. A simple contrast may therefore reflect the circumstances surrounding the habit as well as the habit itself. The source does not test what happens when an otherwise comparable older person starts sauna or resumes it after stopping.
Which quality-of-life result was reported?
Selected RAND-36 domains were better among current users, including physical function, vitality, social functioning and general health. That is more specific than saying every aspect of quality of life or every clinical measurement improved. The instrument and domain names should remain attached to the association.
A questionnaire domain captures reported health-related experience in its intended framework. It is not a direct measurement of survival, disease reversal or the isolated effect of heat. A reader interested in social functioning can inspect that domain while recognizing the same selection concerns. The finding does not establish a universal social effect simply because a social-related measure appears in the instrument.
Why are health and mobility especially important here?
The source reports that reduced sauna use was sometimes related to mobility problems or health reasons. This provides a concrete route for reverse causality: people with better functioning may be more able to continue the activity, while poorer health may contribute to stopping.
That possibility does not demonstrate that sauna contributes nothing. It means the direction and amount of causation are unresolved by a cross-sectional comparison. The reported association is therefore most useful when read as a description of current users and nonusers in this selected group. Ignoring why participation changes would make a plausible influence on both the exposure category and quality-of-life outcome disappear from the story.
| Design feature | Why it matters | Unsupported extension |
|---|---|---|
| Very-old male survivors | Survival and response select the sample | Every older population is represented |
| Current users versus nonusers | Some nonusers discontinued an earlier habit | Lifelong use versus lifelong nonuse |
| Selected RAND-36 domains | Domain-specific associations | Every health outcome improved |
| Mobility-related stopping | Health can influence the exposure category | Continued use necessarily caused better function |
Does statistical adjustment remove those concerns?
The abstract reports that some differences remained after accounting for recorded disease and mobility-disability information. That makes the analysis more informative than ignoring those variables. It still does not guarantee complete measurement of health, access or the reasons for continuing and stopping.
Adjustment also does not convert the survey into a randomized trial or remove the survivor selection built into the sample. A full appraisal would inspect the model, measurement and missing information. The correct interpretation preserves both the adjusted observation and its limits, rather than presenting persistence after adjustment as proof that sauna caused the better domain scores.
Did the reported habits identify an ideal older-adult schedule?
No. The respondents described their existing practices, with many moderating or reducing use as they aged. Those habits are not an allocated dose comparison and cannot identify a universally effective or suitable schedule. A current-user pattern should not become instructions for a person with different circumstances.
The historical safety review supplies separate general cautions but cannot clear every older reader. Personal suitability depends on an individual clinical context that a questionnaire association cannot assess. The useful takeaway is to understand who continued, what they reported and why that comparison has limits, rather than copy an exposure solely because long-lived respondents described it.
How do other quality-of-life designs help interpret this source?
The northern Sweden population survey also found current users differed demographically and in lifestyle alongside reported health. It reinforces the need to examine who uses sauna, without becoming a replication of these very-old men’s specific domain scores. Its recruitment frame and age range were different.
The Korean short program instead measured before-and-after ratings in selected adults, without an untreated comparator described. That design addresses change over a brief period rather than a current-use survivor comparison. Reading the sources together shows that a shared quality-of-life label can cover different questions. Neither supplies the missing causal comparison or long-term outcome for the other.
What remains open after this summary?
This review uses the indexed abstract and verified source abstraction. Full recruitment, nonresponse, modeling and formal risk-of-bias methods have not been comprehensively appraised. Funding and conflict-of-interest disclosures remain unreported in the abstraction rather than assumed absent.
The justified conclusion is an association between current sauna use and selected quality-of-life domains among very old male survivors. Health, mobility and selection can influence continued participation, and the source cannot establish that starting sauna improves survival or produces the same scores. The finding is valuable as a bounded observational description, with universal routine and clinical-suitability claims left unsupported.
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Questions, considered
Questions about this study
Did the Helsinki Businessmen Study prove sauna improved quality of life in very old men?
No. It found cross-sectional associations between current sauna habits and several quality-of-life domains. Health and mobility can determine whether someone continues using sauna, so the direction may run partly from better function to continued use. The authors explicitly identified reverse causality as an important limitation.
Follow the sourceWhy did some older men reduce or stop sauna use in PMID 29188579?
Reported reasons included mobility problems and diverse health concerns, alongside nonspecific explanations. That pattern matters when comparing users with nonusers: the groups may differ because illness makes sauna less accessible. A favorable wellbeing score among current users cannot automatically be attributed to the heat exposure itself.
Follow the sourceCan the octogenarian-men survey establish a universal routine for older adults?
No. It described existing habits among surviving participants in a particular Finnish male cohort. Those habits are observational descriptions, not assigned protocols. Women, people living in institutions, adults with greater disability and those unfamiliar with sauna may face different circumstances that the survey cannot adequately represent.
Follow the sourceFollow the evidence
Sources & references
Research summaries in this edition are based on indexed abstracts unless otherwise noted. A source link is not a claim of medical review.
- Sauna bathing, health, and quality of life among octogenarian men: the Helsinki Businessmen Study.
Strandberg TE, Strandberg A, Pitkälä K, Benetos A
Volume 30, issue 9, pages 1053-1057 · PMID 29188579
Open-access flag: not recorded.Abstract-level editorial review - Sauna bathing in northern Sweden: results from the MONICA study 2022.
Engström Å, Hägglund H, Lee E, Wennberg M, Söderberg S, Andersson M
Volume 83, issue 1, pages 2419698 · PMID 39446139
Open-access flag: yes.Abstract-level editorial review - Repeated Dry Sauna Therapy Improves Quality of Life in Obese Korean People.
Choi HS, Kwon H, Cho KH, Thuc LC, Park SY, Kim NH, Kim WJ, Kim YK, Jeon WS, Lee JA, Kim HC, Cho EH
Volume 41, issue 5, pages 312-317 · PMID 32434303
Open-access flag: yes.Abstract-level editorial review - Benefits and risks of sauna bathing.
Hannuksela ML, Ellahham S
Volume 110, issue 2, pages 118-126 · PMID 11165553
Open-access flag: not recorded.Abstract-level editorial review