Affiliation: Professor of Internal Medicine, University of Eastern Finland. Head of Department, Central Finland Health Care District. Cardiologist and principal investigator of the Kuopio Ischaemic Heart Disease (KIHD) Risk Factor Study.
Jari Laukkanen’s research is the reason the cardiovascular case for sauna stopped being folk wisdom and became evidence. His twenty-year prospective cohort work in Finland produced the first large-scale clinical data tying sauna frequency to lower cardiovascular and all-cause mortality. The numbers Sisu shares with members about heat exposure and longevity come almost entirely from his lab.
Key contribution
The 2015 study published in JAMA Internal Medicine followed 2,315 middle-aged Finnish men over a median of 20.7 years. The findings were striking. Compared with men who used the sauna once per week, those who used it 4 to 7 times per week had:
- 50 percent lower risk of fatal cardiovascular disease
- 40 percent lower risk of all-cause mortality
- Lower incidence of sudden cardiac death
The relationship was dose-dependent. Higher weekly frequency and longer per-session times (up to roughly 30 minutes, where the curve plateaus) both predicted lower risk. These were not casual observations. They came from a large, prospectively designed cohort study with adjustment for cardiovascular risk factors, smoking, alcohol intake, and physical activity.
Subsequent work from Laukkanen’s group has extended the findings to dementia, hypertension, chronic respiratory disease, and overall biological aging markers. His 2024 review with Setor Kunutsor in Temperature synthesized two decades of heat therapy research into a clinical framework that informs how Sisu thinks about sauna as a longevity intervention.
How Sisu applies this work
Three elements of Sisu’s heat protocol come from the Laukkanen body of work.
- Frequency targets. Sisu’s heat education guides members toward 2 to 7 sauna sessions per week, with the dose-response benefits accruing across that range.
- Per-session duration. Sessions of 15 to 20 minutes are the practical sweet spot, consistent with the per-session benefit curve in his cohort, with diminishing returns past 30 minutes.
- Authentic Finnish sauna design. The KIHD cohort were Finnish men using traditional Finnish saunas, not infrared cabins or low-temperature variants. Sisu chose the traditional design specifically because that is the form factor the cardiovascular evidence is built on.
The practical heat protocol is detailed in our Contrast Therapy guide, with the full citation list in our Contrast Therapy white paper.
Where to learn more
- Faculty profile: Professor Jari Laukkanen at the University of Eastern Finland
- Publications: Google Scholar profile
- Key paper: Laukkanen, T., Khan, H., Zaccardi, F., & Laukkanen, J. A. (2015). Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Internal Medicine, 175(4), 542-548. DOI: 10.1001/jamainternmed.2014.8187
- 2024 review: Laukkanen, J. A., & Kunutsor, S. K. (2024). The multifaceted benefits of passive heat therapies for extending the healthspan. Temperature, 11(1), 27-51. DOI: 10.1080/23328940.2023.2300623
