Published in the American Journal of Hypertension, the study of 1,621 men with normal blood pressure, ages 42 to 60, followed the participants an average of 25 years. The findings: The men who went to saunas two to three times a week were 24 percent less likely to have hypertension than those who went once a week or less. Those who took four to seven saunas a week reduced their risk by nearly half (46 percent). The study controlled for variables such as age, body mass index, smoking and family history of hypertension.
The study’s senior author, Jari A. Laukkanen, professor of medicine at the University of Eastern Finland, told the New York Times that while the study does not prove cause and effect, there were a few possible explanations. The sauna’s warmth improves the suppleness of blood vessels, which increases blood flow. Sweating serves as a diuretic, reducing excess body fluid. And a Finnish sauna typically involves warmth and then cooling, which is relaxing, and could reduce blood pressure.
“A healthy thing that is pleasant to do and involves no sacrifice,” he told the Times.