Sweating has long been used as a therapy. The Mayans used sweat houses 3,000 years ago, according to Harvard Health Publications. In Finland, saunas have been used for thousands of years, and 1 in 3 Finns still use them. In the United States (U.S.), there are thought to be over a million saunas.
The main benefits proposed for saunas are for relaxation and cardiovascular health. However, a sauna may not be suitable for everyone.
Fast facts on saunas:
Here are some key points about saunas. More detail is in the main article.
A sauna is a room in which people aim to relax in dry heat.
It may provide benefits for cardiovascular health that resemble those derived from exercise.
Drinking alcohol before or during a sauna can be dangerous.
Anyone who has a cardiovascular problem or who is pregnant should seek medical advice before using a sauna.
What is a sauna?
A sauna helps relax, and it may have other health benefits, too.
A sauna is typically a room heated to between 70° to 100° Celsius or 158° to 212° Fahrenheit.
Traditional Finnish saunas usually use dry heat, with a relative humidity that is often between 10 and 20 percent. In other sauna types, the moisture is higher. Turkish-style saunas, for example, involve a greater level of humidity.
A sauna use can raise the skin temperature to roughly 40° Celsius or 104° Fahrenheit.
As the skin temperature rises, heavy sweating also occurs. The heart rate rises as the body attempts to keep cool. It is not uncommon to lose about a pint of sweat while spending a short time in a sauna.
Types of saunas
There are several types of sauna, based on how the room is heated.
Wood burning: Wood is used to heat the sauna room and sauna rocks. Wood-burning saunas are usually low in humidity and high in temperature.
Electrically heated: Similar to wood-burning saunas, electrically-heated saunas have high temperatures and low humidity. An electrical heater, attached to the floor, heats the sauna room.
Infrared room: Far-infrared saunas (FIRS) are different to wood-burning and electrically-heated saunas. Special lamps use light waves to heat a person's body, not the entire room. Temperatures are typically lower than other saunas, but the person sweats in a similar way. Usually, infrared saunas are about 60° Celsius.
Steam room: These are different from saunas. Instead of dry heat, a steam room involves high humidity and moist heat.
Possible health benefits
Regardless of how a sauna is heated, or the humidity level, the effects on the body are similar.
When a person sits in a sauna, their heart rate increases and blood vessels widen. This increases circulation, in a similar way to low to moderate exercise depending on the duration of sauna use.
Heart rate may increase to 100-150 beats a minute while using a sauna. This may bring some health benefits.
Increased circulation may help reduce muscle soreness, improve joint movement, and ease arthritis pain.
Reducing stress levels
As the heat in a sauna improves circulation, it may also promote relaxation. This can improve feelings of well-being.
Improving cardiovascular health
The reduction in stress levels when using a sauna may be linked to a lower risk of cardiovascular events.
One study, conducted in Finland, followed 2,315 men ages 42 to 60 over the course of 20 years. Findings suggested that people who use a sauna may have a lower risk of dying from cardiovascular disease.
Of the participants in the study, a total of 878 died from cardiovascular disease, coronary artery disease, or sudden cardiac death. Participants were categorized by how often they used a sauna, including once a week, two to three times a week, and four to seven times a week.
After adjusting for cardiovascular risk factors, increased sauna use was linked with a reduced risk of fatal cardiovascular-related diseases.
Participants who used the sauna two to three times a week were 22 percent less likely to experience sudden card