Dry saunas typically achieve higher internal temperatures than their wet counterparts. This is because dry saunas don't waste energy converting liquid water into water vapor, but instead put all of their energy into generating heat. Some dry saunas can produce temperatures of nearly 200 degrees Fahrenheit, as Sauna Talk notes.
While not as hot as dry saunas, wet saunas are more humid, which makes for a considerable difference in heat perception. Dry saunas typically have humidity levels of around 10 percent, while wet saunas, in comparison, can attain humidity levels of between 20 and 30 percent. The high humidity levels of wet saunas can cause people to perceive that wet saunas are hotter than dry saunas, even when the actual air temperature indicates otherwise. This is because the human body has difficulty dissipating body heat when the surrounding air is full of moisture. When the body sweats in an effort to cool down, the moisture in the air prevents sweat molecules from evaporating. In contrast, when exposed to the dry heat of a dry sauna, sweat molecules evaporate readily, allowing the body to feel cooler.
Because the body is never allowed to cool down in a wet sauna due to humidity, sitting in a wet sauna causes you to sweat more in comparison to sitting in a dry sauna. The benefit of sweating is that it helps to clean oils and dirt out of the skin's pores. In addition, sweating can help detoxify the body, as sweat contains urea. Urea is one of the waste compounds the body produces following protein metabolism.
In addition to being better at encouraging sweating, wet saunas are better than dry saunas at providing people with relief from allergies and respiratory problems, such as asthma and bronchitis. This is because the moist air of wet saunas can help sooth irritated tissues and loosen phlegm and mucus.
If you are using or planning to use a sauna for losing weight, home improvement website Repair-Home says the best option is to use a dry sauna. While a wet sauna causes increased sweating, a dry sauna increases heart rate and metabolism. And while sweating can help you lose water weight, increasing your heart rate can help you improve blood circulation; while increasing metabolism can help you burn stored, permanent fat.