Sauna: the dose the research actually used

By Ronen Shapiro · Last reviewed 2026-08-05 · How this is sourced

Sauna is the closest thing to a cardiovascular drug that is not a drug — and it is also one of the most over-claimed protocols on the internet. Here is what the main cohort found, at what dose, and what an observational study can and cannot tell you.

The dose

The Laukkanen cohort followed 2,315 middle-aged Finnish men for a median of roughly 20 years, using traditional dry Finnish sauna. Compared with one session per week, 4–7 sessions per week was associated with lower cardiovascular mortality and lower all-cause mortality. Session length mattered too: 20+ minutes was associated with more benefit than under 11 minutes.

• Laukkanen et al., JAMA Internal Medicine, 2015. View study

What it cannot prove

This is a prospective cohort study, not a randomised trial. It shows an association. People who sauna 4–7 times a week may be healthier, wealthier, or more able to exercise in the first place, and no statistical adjustment fully removes that. The honest summary is that frequent sauna use travels with better cardiovascular outcomes — not that it has been proven to cause them.

The mechanism people skip

Heat stress raises heart rate and cardiac output in a way that overlaps with moderate exercise, and induces heat shock proteins involved in protein-folding quality control. There is also randomised evidence for an antidepressant effect of whole-body hyperthermia, which is a separate finding from the mortality data and should not be merged with it.

Ordering it with cold and with lifting

If you are combining heat and cold, note that cold immersion within about 4–6 hours after strength training appears to blunt some hypertrophy signalling. Sauna does not carry that specific caveat. Read the cold protocol for the timing detail.

• Søberg et al., Cell Reports Medicine, 2021. View study

Common questions