They are lauded as an easy way to lose weight – but regular sauna visits could also help stave off strokes.
Those who go between four and seven times a week are 61 % less likely to have a stroke than those who go once, a study shows.
The more frequently saunas were taken, the lower the risk of stroke.
Researchers believe the high temperatures can help to reduce blood pressure – a leading cause of stroke – as well as boost the immune system and keep the heart and blood vessels healthy.
‘These results are exciting because they suggest that this activity that people use for relaxation and pleasure may also have beneficial effects on your vascular health,’ said Setor Kunutsor, who led the study at the University of Bristol.
‘Sauna bathing is a safe activity for most healthy people and even people with stable heart problems.’
The researchers studied 1,628 people over a period of 15 years in Finland, where most homes are equipped with saunas.
The participants, who had an average age of 63 and no history of stroke, were questioned about sauna habits and other lifestyle factors, such as physical activity and alcohol consumption. During the study follow-up period, 155 of the participants had a stroke.
Those who took more saunas were less at risk, according to the findings published in the journal Neurology. The results were the same after researchers adjusted for other factors that could affect stroke risk, such as high cholesterol, smoking and diabetes.
Dr Kunutsor said a limitation of the study was that it was based on traditional Finnish saunas and the results could not be applied to other types of heat therapy such as infrared heat exposure, steam rooms and hot tubs.
Doctors say elderly people with low blood pressure should use caution when taking a sauna.