A trip to the sauna might be the answer for Britons struggling to cope with the long, hot summer of heatwaves, according to scientists.
Research suggests that exposure to high temperatures may help the body acclimatise to the heat and allow it to regulate its temperature more efficiently.
The UK is currently suffering through its fourth heatwave of the year, with amber and yellow heat health alerts in place across England after the UK Health Security Agency warned rising temperatures would increase health risks.
Meanwhile, there has been a rise in saunas popping up across the country, with the British Sauna Society now listing 853 saunas across the UK, up from 640 in April, and 45 in 2023.
Professor Jari Laukkanen, a cardiologist at the University of Eastern Finland, argues that repeated exposure to heat might help the body build up a tolerance.
The scientist, whose research focuses on the positive impacts of regular sauna use on cardiovascular health, told The Guardian that heat adaptations include earlier and more efficient sweating, improved skin blood flow, expansion of plasma volume, and reduced cardiovascular strain, which can help regulate body temperature more efficiently.
“This is well established in sports physiology, where athletes deliberately use repeated heat exposure to improve heat tolerance before competing in hot environments,” he told the newspaper.
“Indeed, quite similar physiological adaptations may also occur with passive heat exposure, such as sauna bathing and hot water immersion.”
One of his studies, which was published earlier this year, found that a single 30-minute sauna session paired with a short cold shower can increase every type of white blood cell circulating in the bloodstream.
A separate study, published in the Journal of Applied Physiology, found that passive heat therapy can improve cardiovascular function and general health status in middle-aged and older adults, which could decrease cardiovascular strain during heat exposure and mitigate heat-related health risks.
Mr Laukkanen told The Guardian that building up a tolerance to hotter temperatures would not protect the body from illnesses but could help it adapt.
He said there was “limited evidence that going to a sauna during a heatwave itself protects people from heat-related illness or other conditions.
“The benefits are more likely related to long-term adaptation through regular heat exposure rather than using a sauna as an acute treatment during very hot weather.”
A report in March found that the UK’s sauna market generated a revenue of £62.88m in 2025 and is expected to reach £110.27m by 2033, possibly making it the largest in Europe.
