You might have heard that having a sauna once in a blue moon is good for your health. Sauna definitely helps with weight loss and has many health benefits, but how many calories can you actually burn in a sauna and can it actually be used as a method for weight loss?

Measuring calories burnt in a sauna

In order to create an original and at least a marginally scientific article, we did not just rely on the combined knowledge of the web. We carried out a test. On a proper sauna boat in Oslo, Norway!

Our test subject was our sales guy Leho, the test equipment an Oura Ring, that tracks your sleep patterns and daily activity, and creates recommendations based on how your stats have changed over the recent days. In addition to great hardware, Oura has developed a sleek app to display you all the metrics along with a relative aptitude for pushing your limits that day (they call this a Readiness Score). Leho has been wearing Oura for almost two years now and now sleeps like a baby. Almost every night.

In the sauna we go!

Much like the Finns, almost every Estonian has a sauna in their back yard, so we would have been able to give it a go anywhere. However, since we were visiting our friends at GreenBoats at the time, we thought there couldn't be a better location for our test but a true sauna boat in the heart of Oslo.

Everybody at Greenies is super friendly and welcoming, so if you don't have a sauna in your back yard, and you happen to be in Oslo, you need to book a sauna at GreenBoats. They have even named the seagulls that like to visit daily. Well, that’s customer service lvl 3000.

Defining a baseline

The test started at around 1pm with a lovely view to the Oslo marina, not a single cloud at sight. Since Leho is not the smallest of guys, sporting around 105 kilos, he would be inclined to burn a little more than an average person. At the start of our one-hour sauna ritual, he had managed to burn 415 kCal that day.

During the sauna ritual

To be scientifically more accurate about the conditions, we like a very hot sauna, like our fathers and grandfathers did. It almost seemed like they were trying to steam us out of the sauna back in the old days. Or toughen us up. Anyway, in Oslo, we did two 12-minute sauna sessions at 100-120 degrees celcius.

One exceptionally good thing about GreenBoats is that they are right at the Aker Brygge marina, offering a cold dip in water whenever you like. We Estonians know how much extra “oomph” we can get from going for a swim or rolling in snow after a sauna session. All in all,  24 minutes of steaming sauna with a lovely view.

In a sauna you can burn about 1 kCal a minute

At the end of this 56-minute sauna experience, including swimming and having a blast, Leho’s app showed 476 kCal, meaning that in total he managed to burn 61 kCal or roughly about 1 kCal a minute during the sauna session. 

Screenshots from Oura App before and after


The experiment was fun, no question about it. However, sauna alone cannot be a good weight loss strategy. Additionally, you need exercise, good nutrition and high-quality sleep. A sauna can be a very good supporting strategy, if you do it right. Drink lots of water before, during and after a sauna, and you are definitely on track.

Sleep quality the night after the sauna

Oura will be able to tell you about your sleep quality and what might affect it. For example, even a slightly bigger snack too close to bedtime will affect your sleep and usually not in a positive way. The same thing applies to sauna. Perhaps because our sauna session was not directly before bed but at noon, Leho’s sleep quality was surprisingly high. He was able to hit one of his targets for lowest resting heart rate of 37 bpm during the night after the sauna.