In the early 1980s, a group of scientists set out to conduct a long-term study on heart health.
They focused on Finnish men, recruiting over 2,000 participants and monitoring everything from their behaviors, diets, lifestyle choices, and fitness over the course of 20 years.
As they dug into the data, researchers were stunned to find that one habit — something they hadn't expected — was linked to better health: frequent sauna bathing.
Yet, this likely didn't surprise the Finnish participants.
Finland is a country with 9,000 years of sauna traditions.
And they're not alone: Roman balneae, Japanese onsen, and Indigenous American sweat lodges are just a few examples of how cultures across the globe have long considered exposure to extreme temperatures therapeutic.
But today, scientists are only just beginning to unravel how and why this may be the case.
So, what exactly is happening in your body when you feel the heat?
To understand how extreme heat affects the body, let's explore what happens when you enter a sauna.
Traditional Finnish sauna temperatures can top out at 90°C, or just below the boiling point of water, and are typically dry, at about 20% humidity.
