The science and benefits of sauna use

Saunas have been around for thousands of years and were popularised by the Finnish. But do they have any actual health benefits or are they just a sweat-inducing hoax? We look at the science behind sauna use and speak to GP Dr Michela Sorensen to uncover the truth. 

A sauna is a small room that is generally heated to anywhere between 70C and 100C. Sauna-goers sit in the room for short periods of five to 20 minutes. As their skin temperature rises from the normal range of around 33C to 41C, they begin to sweat to regulate their body temperature. Their heart rate and blood pressure also increase.  

Many people report feelings of relaxation after using a sauna. 

The types of saunas and what they do 

There are three main types of saunas: 

• Dry saunas: Traditional Finnish saunas are wood-burning, but dry saunas can also be electrical. In a dry sauna, the humidity is low. 

• Steam saunas: Also known as steam rooms or steam baths, these saunas have very high levels of humidity. 

• Infrared saunas: While purists don’t consider infrared saunas to be true saunas, these also raise body temperature and cause sweating. Instead of heating the whole room, infrared light waves are used to heat the body directly. 

“To date, studies suggest all forms of sauna have equal health benefits,” says Michela. 

“Saunas have been used for many years for their relaxation benefits,” says Michela. “They are known to reduce stress and anxiety. Increasing evidence also shows a variety of physical benefits, including improved cardiovascular health, pain reduction and even an improvement of asthma symptoms in some people. 

“There is emerging evidence to suggest a link between sauna use and a reduced risk of Alzheimer’s disease, but this is an area that requires more research.” 

If you’re a healthy adult and you’d like to try a sauna to see if you reap any physical or mental health benefits, there are a few things to consider first. 

Things to keep in mind and look out for 

Start with short sauna visits and build up gradually. You might use the sauna for five minutes the first time and slowly increase to 20 minutes. While some people stay in saunas for longer periods, 20 minutes is generally considered the safe limit. 

Make sure you hydrate well before and after using the sauna to replace lost fluids. Never use a sauna when you’re under the influence of alcohol because it can affect your body’s ability to maintain blood pressure and can lead to heatstroke or accidents. 

When to seek medical advice 

You should seek medical advice before using a sauna if you’re pregnant or have a chronic health condition. 

“Caution needs to be used in anyone with a history of kidney problems due to the risk of dehydration,” says Michela. “Additionally, anyone with poorly controlled blood pressure – both high and low – should see their doctor beforehand.” 

Please note: The tips throughout this article serve as broad information and should not replace any advice you have been given by your medical practitioner.