6 Sauna Health Benefits: A Science-Backed Guide to Heat Therapy for Health

As the only Finnish word in the English dictionary, saunas are an inherent part of the culture in Finland, dating as far back as 7,000 BCE.

Although saunas were brought to America by Finnish settlers in the 1600s, the practice of saunaing for health did not take off in the U.S. until the 20th century. 

Now, researchers have uncovered what Finns have known for millennia—that sauna bathing has immense health benefits, ranging from cognitive and cardiovascular to pain relief and stress support. 

In this article, learn more about the top sauna health benefits or heat therapy and the best practices for utilizing the sauna for your health and longevity. 

What Is Sauna?

If you’ve heard the term sauna before but never known quite what goes on inside those little rooms, here’s a brief summary.

The Finnish word “sauna” translates to “bath” or “bathhouse,” as traditional Finnish saunas were seen as a sterile and sacred place for cleansing, detoxing, and relaxing. 

Saunas—correctly pronounced “sow-nah” (rhyming with “wow”), not “saw-nah”—involve a small, enclosed room, most often wood-paneled with wooden benches. Hot sauna rocks or stones are doused with water to release steam and increase humidity (a process called löyly), raising the temperature to 140–195° Fahrenheit and humidity to 5–40%. 

However, Finnish saunas are not always steam saunas—they can also be dry. Dry heat saunas do not add excessive humidity via steam but rather generate dry heat with wood-burning stoves, electric heaters, or hot rocks. 

Now, many saunas use infrared heat instead of the hot rocks and steam method. Finnish saunas are much hotter than infrared saunas, which use lower temperatures and infrared radiation to directly heat the body instead of steam and humidity.

Infrared saunas are still hot—110 to 140° F—but much more tolerable than steam saunas as they don’t raise humidity.

Both infrared and traditional sauna sessions provide immense health benefits, which is due in large part to a concept called hormesis. 

What Is Hormesis?

Hormetic stressors are environmental or physiological conditions that put moderate amounts of stress on the body—a state known as hormesis—which has the end result of increasing resilience to stress.

Exercise is the most well-known hormetic stressor, but heat therapy (like sauna use), cold exposure (like ice baths or cold showers), and fasting also stimulate hormesis.

Elevated temperatures seen in heat therapy (like saunas) trigger hormesis-related responses to core body temperature balance, including an increased production of heat shock proteins (HSPs).

Heat shock proteins (sometimes known as stress proteins) are vital for maintaining protein homeostasis, DNA repair, and protecting against cellular stress. Dysfunctional HSPs are linked to disease development, including cancer, neurodegenerative disease, cardiovascular conditions, and autoimmune disorders.¹

In moderate amounts, hormesis activates beneficial cellular responses and defense mechanisms that increase your resilience in the future. The key word is moderate—just as exercising for 12 hours per day would be detrimental to your body, so would excessive sauna use. 

Essentially, hormesis is the definition of “what doesn’t kill you makes you stronger,” and sauna use is one way to activate it.

Sauna Health Benefits

Many of the health benefits from sauna bathing come from the hormesis mentioned above, but the elevated temperatures themselves also provide some of the benefits due to increased blood circulation. 

1. Cardiovascular Health

One of the most-studied benefits of sauna use is cardiovascular health. Heat stress promotes the widening of blood vessels (known as vasodilation) and blood flow, lowering blood pressure.

Heat is also linked to reduced inflammation and helps the heart muscles be more efficient with pumping blood and delivering oxygen to other tissues in the body. 

One study of over 2,300 Finnish men found that those who used the sauna 2–3 times per week experienced a 27% reduction in the risk of dying from cardiovascular events than men who did not use the sauna.² More benefits were seen with increased sauna use, as men who used the sauna 4–7 times per week had a 50% risk reduction in heart disease mortality. 

Another study looked at both men and women, finding that the risk of cardiovascular disease mortality reduced strongly and linearly with increasing sauna use—meaning the more times people saunaed, the lower their risk of dying from heart disease was.³

In this group of middle-aged and older adults (average age 63), saunaing 4–7 times per week reduced the risk by 77% compared to those who used the sauna once per week. 

2. Cognitive Health

Sauna benefits the brain due to increased blood flow and an increased expression of BDNF (brain-derived neurotrophic factor). BDNF is essential for the growth and maintenance of adult neurons, a process known as neurogenesis.

Research has shown that higher BDNF activity is linked to better cognitive function and memory.⁴ One small but interesting study found that serum BDNF levels increased by 66% after healthy males were immersed (head out) in 108°F water for 20 minutes.⁵ Although this isn’t quite the same as sitting in a sauna, it is still suggestive of the benefits of heat therapy. 

Other research with Finnish adults found that frequent sauna users (9–12 times per month) had a 53% reduced risk of developing dementia during a 39-year study compared to those who saunaed less than 4 times per month.⁶

3. Stress Relief and Mental Health

As long as you are not overheating, sitting in the sauna can be very relaxing, contributing to stress relief and mental health. 

The study with head-out hot water immersion from the previous section also measured cortisol levels—our body’s primary stress hormone—finding that hot water immersion also significantly reduced cortisol.⁵  

Although heat therapy is an acute stressor, its hormetic nature means that it builds resilience to stress over time. 

This was seen in a study based on the Global Sauna Survey, in which almost 500 regular sauna users responded to a questionnaire.⁷ The results showed that sauna users (5–15 times monthly) had higher mental well-being scores, and one of the key reasons for their continued sauna use was relaxation and stress reduction.

4. Pain Relief

People with acute or chronic pain (acute being something like muscle soreness or a fleeting injury and chronic being related to a disease like rheumatoid arthritis or fibromyalgia, for example) can benefit from sauna use. 

Sauna or heat therapy helps with pain for several potential reasons, including reducing inflammation, increasing blood flow, and promoting relaxation.

In the Global Sauna Survey, of the one-third of respondents with a medical condition, people with chronic back or musculoskeletal pain reported the greatest improvements in their conditions from regular sauna use.⁷

Another study looked at dry sauna use (i.e., just heat and no steam), finding that people with chronic low back pain saw significant improvement in their pain levels from regular use.⁸

5. Muscle Mass Maintenance and Recovery

Many athletes and exercise enthusiasts use saunas to soothe sore muscles after intense physical activity—but research also shows that saunas can promote muscle mass maintenance. 

Heat shock proteins have been found to slow down muscle atrophy, which leads to sarcopenia or muscle loss. They also can prevent muscle protein damage by reducing oxidative stress and boosting cellular antioxidant levels, supporting overall muscular health. 

One small study with 23 healthy young males found that those who used a high-temperature (212 °F) sauna 12 times had improved bone and muscle mass, including increasing the muscle mass of the right leg and bone mineral density of the left leg.⁹

6. Immune System Support

Lastly, regular sauna use has been shown to benefit some aspects of immune system health, including reducing the risk of certain infectious diseases. 

In a study of almost 2,000 middle-aged men, regular sauna use significantly reduced the risk of acute and chronic respiratory conditions, including chronic obstructive pulmonary disease (COPD), asthma, and pneumonia.¹⁰ The greatest benefit (41% lower risk) was seen in those using the sauna more than 4 times per week. 

It’s likely that saunas improve respiratory-related immune health due to the clearance of pulmonary congestion and improving lung function. However, excessive steam can sometimes make existing respiratory conditions worse, including COPD and asthma.

How to Use Sauna for Health and Longevity

Like most things in life, moderation is key. You don’t want to sit in the sauna all day long, but regular use can potentially provide the benefits listed above. 

Whether you decide to use infrared sauna or traditional saunas (steam or dry) is up to you, as they seem to provide relatively similar benefits. If you are heat- or humidity-sensitive, consider the infrared sauna. 

Here are some tips and best practices for using a sauna:

• Take a quick shower before (especially if you just worked out)
• Hydrate before, during, and after your sauna session 
• Get out if you feel overheated, dizzy, or lightheaded
• Start with 5-10 minute sessions and work your way up to 20 minutes
• Never use the sauna when intoxicated (alcohol or drugs)
• Use proper sauna etiquette if using a shared sauna (i.e., sit on a clean towel, keep noise to a minimum, dress appropriately, and mind how much space you are taking up)  

Potential Sauna Contraindications

Saunas are not for everybody. Some people who should not use a sauna or need to ask their doctor first include:

• Those who are pregnant
• People with medical conditions like uncontrolled high blood pressure, diabetes, heart failure, epilepsy, anemia, or heart arrhythmias
• People who are currently sick, including having a fever or the flu
• People with open wounds or infections
• When you are or have been drinking alcohol or taking drugs 

Ask your doctor if you are unsure if you can use a sauna. 

Benefits of Sauna Bathing FAQs