Sauna and Cold Plunge: What Long-Term Research Suggests About Heat, Cold, and Heart Health
March 4, 2026
Research published in JAMA Internal Medicine explored how regular heat exposure through sauna bathing relates to long-term cardiovascular health. In the study, researchers followed more than 2,300 middle-aged men in Finland for over 20 years, tracking their sauna habits and health outcomes. The results showed a clear trend: people who used the sauna more frequently had a significantly lower risk of sudden cardiac death and fatal heart disease. Participants who used the sauna two to three times per week had lower risk, while those who used it four to seven times per week experienced the greatest reduction in cardiovascular mortality compared with those using it only once weekly. These findings suggest that consistent heat exposure may support long-term heart health.
Researchers believe these benefits are largely due to how the body responds to changes in temperature. Heat exposure increases heart rate and expands blood vessels, improving circulation and placing a mild, exercise-like demand on the cardiovascular system. When heat is paired with cold exposure—such as a cold plunge following a sauna session—the circulatory effects may be amplified. Heat causes blood vessels to expand while cold causes them to constrict, creating a natural “vascular workout” that stimulates circulation and helps the body adapt to stress. This process, often referred to as contrast therapy, is increasingly used in wellness and recovery practices to support cardiovascular function, circulation, and overall resilience.
