Types of sauna: Finnish, infrared, steam room and banya compared

Finnish sauna

The classic: a wood-lined room heated by an electric or wood-burning stove covered in stones. Air temperature is usually 70°C to 100°C, highest near the ceiling, and humidity is low until you throw water on the stones to make löyly, a short burst of steam that makes the room feel much hotter for a minute or two. People typically stay in for 5 to 20 minutes, cool off, and repeat.

This is the type used in the Finnish studies on heart health, blood pressure and dementia.

Russian banya

A banya runs at similar temperatures to a Finnish sauna but is usually more humid. Many include a venik, a bundle of birch or oak twigs used to whisk the skin, and a cold plunge. The higher humidity makes the heat feel more intense at the same temperature, so sessions are often shorter.

Infrared cabin

Instead of heating the air, an infrared cabin uses panels that give off infrared light, which warms your skin and body directly. The air is cooler, usually 40°C to 60°C, so people stay in longer, often 15 to 40 minutes. Studies of infrared saunas are much smaller than those of traditional saunas; the best-known are Japanese studies of a 60°C version called Waon therapy for heart failure. Infrared vs traditional compares the two in detail.

Steam room

Also called a hammam or Turkish bath. The air is only around 40°C to 50°C, but it is saturated with moisture, so your sweat can’t evaporate. That means your body heats up faster than the number suggests, and 10 to 20 minutes is plenty for most people. Steam rooms have had very little dedicated health research.

Hot tub or hot bath

Not a sauna, but it heats you in a similar way. Water at 37°C to 40°C transfers heat into your body much faster than air, so core temperature can rise quickly. American trials of regular hot-water immersion found improvements in blood vessel function and blood pressure similar to those seen with saunas.

Does the temperature reading tell you how hot it is?

Not on its own. The sauna thermometer is usually mounted high on the wall, where it is hottest. The top bench can be tens of degrees hotter than the floor, so moving down a bench is the easiest way to make a session gentler. Humidity matters as much as temperature: 45°C in a steam room is harder going than 80°C in a dry sauna.