Saunas are springing up across Britain in fields, horseboxes, barrels and beach huts, with the British Sauna Society now listing about 640 saunas – up from 540 at the start of the year. A recent report predicts the UK could become the world's largest sauna market by 2033, outpacing Finland and Germany.
“The continuing growth suggests that the peak has still yet to come – if there is one,” said Gabrielle Reason, the society’s director. But are saunas a tonic for the nation’s health – or a wellness fad with hidden risks?
When it comes to measurable health effects, the strongest evidence relates to cardiovascular benefits. Prof Setor Kunutsor at the University of Manitoba in Canada said: “Comparing people who engage in four to seven sauna sessions per week with those who engage once a week, the risk reductions in cardiovascular outcomes range from 40 to 60%.” He added that a randomised controlled trial showed a systolic blood pressure reduction of 8mmHg after eight weeks of three sauna sessions per week.
Precisely how saunas trigger benefits is still being studied, but the general idea is that the body undergoes controlled heat stress, producing responses similar to moderate exercise. As body temperature rises, the heart beats faster and blood flow increases, leading to improvements in blood vessel, heart and lung function, and reductions in blood pressure, inflammation and blood fats.
A new study led by Martha Newson at the University of Greenwich suggests the benefits may run deeper. Analysing data from more than 1,900 UK sauna users, researchers found that regular sauna use was linked to improved physical and mental wellbeing, with the strongest effects among those who used saunas weekly and felt a sense of belonging to a sauna community. “At its most basic, a sauna is people getting stripped off and sitting in a hot room,” said Newson, noting that the combination of shared ritual, physical intensity and vulnerability can forge unusually strong social bonds.
At Fire and Ice Wellness in north Bristol, co-founder Jamie Winn described the experience as an emotional “safety net”. “There’s something about people being in their bathers with nothing to hide, sort of forced to sit opposite each other, they’ll have a conversation and it all feels very natural,” he said.
