More frequent sauna use was linked to lower cardiovascular and all-cause mortality risk in Finnish men

A prospective cohort study followed 2,315 middle-aged Finnish men for a median of nearly 21 years, tracking how often and how long they used saunas alongside rates of sudden cardiac death, fatal coronary heart disease, fatal cardiovascular disease, and all-cause mortality. Men who used a sauna four to seven times per week had substantially lower rates of each outcome compared with those who went only once a week, even after adjusting for established cardiovascular risk factors.

What the study found

Researchers grouped participants by how often they reported using a sauna at the study's outset: once a week (601 men), two to three times a week (1,513 men), or four to seven times a week (201 men). Over roughly two decades of follow-up, the proportion who died from sudden cardiac events, coronary heart disease, or cardiovascular disease declined steadily across those groups.

After accounting for known cardiovascular risk factors, men in the highest-frequency group had a hazard ratio of 0.37 for sudden cardiac death compared with the once-a-week group — meaning their observed risk was roughly 63% lower, though the confidence interval was wide (0.18–0.75). Comparable inverse associations emerged for fatal coronary heart disease, fatal cardiovascular disease, and all-cause mortality, with statistically significant trends across all four outcomes.

Session length also showed an association with some outcomes. Compared with sessions under 11 minutes, sessions exceeding 19 minutes were associated with roughly half the risk of sudden cardiac death and significant reductions in fatal coronary and cardiovascular disease. However, longer sessions were not significantly associated with lower all-cause mortality, making the duration finding more selective than the frequency finding.

Because this is an observational design, the authors themselves note that the associations do not confirm that sauna use caused the lower mortality rates, and they call for further research to clarify the biological pathways that might connect sauna habits to cardiovascular health.

Limits worth knowing

The study enrolled only men aged 42–60 from a single region of Eastern Finland, so findings may not extend to women, younger or older adults, or populations with different baseline health profiles or sauna customs. Sauna frequency and duration were measured only once at enrollment and may not reflect habits over the full follow-up period. The observational design cannot rule out residual confounding — healthier or more socially active individuals may use saunas more often for reasons unrelated to the sauna itself. Funding was disclosed as non-U.S. government support; specific sources are not detailed in the abstract. The study did not capture sauna temperature, type, or the social and relaxation context of sessions, any of which could independently influence outcomes.

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