Does a sauna lower your blood pressure?
Short answer
Yes, blood pressure can fall below baseline after a sauna, but it rises during the heat exposure. In an 8-week randomized trial, adding a 15-minute post-exercise sauna produced about an 8 mmHg larger systolic reduction than exercise alone. Over years, frequent use was associated with a lower rate of developing hypertension, which is an association rather than proof of cause.
Separate during, after, and long term
Sauna does not create one blood-pressure response. Heat raises cardiovascular demand during the session, the immediate post-session reading can fall below baseline, and habitual use has a separate long-term evidence base.
| Timescale | Measured response | Evidence |
|---|---|---|
| During the session | Blood pressure and heart rate rose. | 19 healthy adults, 25 minutes at 93C (199F) and 13% humidity. |
| After the session | Blood pressure fell below baseline. | The same acute cardiovascular-response study. |
| After 8 weeks | About 8 mmHg larger systolic reduction with exercise plus sauna than exercise alone. | A randomized trial with 47 participants. |
| Over a median of 24.7 years | Frequent use was associated with fewer new hypertension cases. | A cohort of 1,621 men without hypertension at baseline. |
Do not treat the post-session reading as the whole story
A lower reading after sauna follows a period when cardiovascular load was higher. Compare measurements at consistent times if you want to know whether a habit changes your baseline rather than capturing only the immediate swing.
Existing cardiovascular conditions are a reason to talk to a doctor about heat exposure and your protocol. The population results do not replace individual medical guidance.
What the research says
Ketelhut and Ketelhut measured blood pressure and heart rate in 19 healthy adults during a 25-minute sauna at 93C (199F) and 13% humidity. Their Complementary Therapies in Medicine study from 2019 found a response comparable to a 60–100 W exercise workload during the session, followed by blood pressure below baseline afterward.
Zaccardi et al. followed 1,621 men without hypertension for a median of 24.7 years and recorded 251 new cases. Their American Journal of Hypertension study from 2017 found that 4–7 sessions a week was associated with a hypertension hazard ratio of 0.53, about 47% lower than 1 session a week. This cohort association does not prove that sauna prevented hypertension.
Lee et al. randomized 47 participants across exercise plus sauna, exercise alone, and control for 8 weeks. Their American Journal of Physiology-Regulatory, Integrative and Comparative Physiology trial from 2022 found that adding a 15-minute post-exercise sauna produced about an 8 mmHg larger systolic blood pressure reduction and a larger total cholesterol reduction than exercise alone. Exercise alone produced the larger fitness gain, about 6.2 mL/kg/min versus about 2.7 mL/kg/min for exercise plus sauna relative to control.
Laukkanen, Laukkanen, and Kunutsor's Mayo Clinic Proceedings review from 2018 summarized cardiovascular and other sauna evidence rather than enrolling a new participant population. It presents acute cardiovascular responses and long-term cohort associations as different forms of evidence.
How Gyroscope does it
Blood pressure comes into Gyroscope through Apple Health and sits on the same timeline as heart rate, resting heart rate, HRV, sleep, and workouts.
Labs can compare sauna days with your own pre-experiment baseline, while the timeline keeps during-session and later readings in their actual context.