In Scandinavia, saunas have long been used as a way to socialize as well as for their many health benefits. And while they aren’t quite as popular in the United States, you can still find saunas in many gyms and community centers.
Saunas are a nice way to relax and have a good sweat, but can they really help you lose weight? The short answer is… sort of.
Researchers still have a lot to learn about how the heat from saunas affects the body.
A sauna is defined as a room that’s heated to temperatures between 150ºF and 195ºF (65.6ºC and 90.6ºC). Finnish-style saunas are considered “dry,” while Turkish style saunas have lots of steam. People typically spend around 15 to 30 minutes in a sauna.
While the temperatures and humidity levels vary, saunas generally work the same when it comes to how your body reacts.
These are the most common types of saunas:
Wood-burning stoves are used to heat sauna rocks. Temperatures are high and humidity is low.
Electrically heated sauna
An electric heater mounted on the floor or wall is used to heat the room. Temperatures are high and humidity is low.
You might also know these as “Turkish bath houses.” Temperatures are low and humidity is high, at 100 percent.
This sauna uses light waves to heat your body without warming the room. The benefits are similar to more conventional saunas.
There is a tiny bit of weight loss happening while you’re in the sauna. That’s because you’re sweating off water weight. Once you begin drinking again, the water weight returns.
The higher temperatures cause your heart rate to increase in a way similar to exercise. But this increase only causes a slightly higher calorie burn than sitting at rest.
The sauna may be able to help you burn some extra calories, but don’t bank on sweat sessions alone to shed pounds. It isn’t an effective tool for real weight loss.
Extreme heat makes your body sweat. When you sweat, you lose fluids. If you lose more fluid than what you’re taking in, you can become dehydrated. There is a risk of getting dehydrated from being in a sauna.
According to Harvard Medical School, the average person loses about 1 pint of fluid during a short time in the sauna. However, if you drink enough water before, during, and after your time in the sauna, you will replace fluids lost by sweating.
Signs of dehydration
Severe dehydration is a medical emergency. It’s important to pay attention to your body and drink plenty of fluids if you use a sauna.
Be aware of these signs of mild to moderate dehydration:
- dryness in the mouth
- extreme thirst
- feeling dizzy or lightheaded
- not urinating as frequently as normal
Older adults and people with chronic conditions such as diabetes, kidney disease, and heart failure, or those who are pregnant, are at a higher risk of becoming dehydrated.
The high heat levels you experience in a sauna cause your blood vessels to open up and move closer to the skin’s surface. When blood vessels expand, your circulation improves, and your blood pressure gets lower.
Some recent studies have found links between regular sauna use and improved heart health. However, people who have heart issues, such as an irregular heartbeat or recent heart attack, are usually told to avoid saunas.
People with high blood pressure can use saunas, but the American Heart Association (AHA) warns against moving between extreme hot and cold temperatures because it can raise your blood pressure. Also, those on heart medications should check with their healthcare provider before using a sauna.
Studies from Finland, Japan, and Germany have found health benefits to regular sauna use. For healthy adults, sitting in a sauna at temperatures around 190ºF (87.8ºC) is considered safe. If you’re pregnant or have a chronic health condition, you’ll want to consult your doctor first.