There is some very promising research that shows the benefits of sauna therapy for cardiovascular disease. A recent systematic review of 40 studies found that both Finnish and infrared sauna bathing was beneficial for people with heart-related disease.

One way infrared sauna bathing is thought to improve heart disease is by significantly reducing a peptide that is commonly elevated in chronic heart failure patients, and by reducing blood pressure.

Steam saunas may also help to prevent hyperglycemia, insulin resistance, and diabetes. A study involving 80 healthy adults found that fasting blood glucose levels (FGBLs) were significantly decreased after seven sauna sessions (over the course of 14 days). High FGBLs are a risk factor for or indicator of insulin resistance and type 2 diabetes.

There are some promising studies that suggest sauna therapy, in particular infrared sauna therapy, improves autoimmune and chronic disease:

Two clinical studies in chronic fatigue syndrome patients using Waon therapy (infrared sauna therapy followed by wrapping in thermal blankets) saw significant improvement of wellbeing metrics.

Fibromyalgia patients who used infrared sauna therapy three times per week for twelve weeks had 31-77% reductions in pain, which for many patients continued after 6 months.

Patients with rheumatoid arthritis or ankylosing spondylitis who used four weeks of infrared sauna therapy in a pilot study saw 40-60% reductions in pain and stiffness.

Studies suggest that regular sauna use may improve your metabolic performance and your ability to gain muscle mass.

A systematic review of 40 studies concluded that infrared sauna use was helpful for athletes trying to improve their performance.

Sauna use increases the secretion of human growth hormones several-fold, a substance your body normally produces after exercise. Human growth hormone causes increased fat burning, muscle building, and endurance.

Several smaller clinical trials have been done on the performance effects of traditional sauna use. Two of these trials showed that post-exercise sauna bathing improved endurance and heat tolerance.

Limited evidence suggests that sauna therapy has some benefits for mental health, though more research needs to be done. For example, six weeks of infrared sauna therapy led to lower depression scores compared to placebo treatment in one study. And frequent sauna use was strongly associated with a lower risk of psychotic disorders in middle-aged Finnish men.

Even more promising are some early studies suggesting there may be some benefit from using sauna therapy for preventing Alzheimer’s disease. A 20 year-long prospective study of Finnish men concluded that 2-7 sauna bathing sessions per week were associated with a reduced risk of dementia and Alzheimer’s disease.

Sauna use is frequently thought of as a tool to help detox your body from chemicals. But is this claim accurate?

A systematic review of observational studies found that repeated sauna use can lead to significant excretion of heavy metals like cadmium, lead, and mercury through the skin.

And a study of police officers who were exposed to methamphetamine fumes in the line of duty saw improvements to sleep, mental health, neurotoxicity scores, and more after completing a program of sauna therapy, exercise, and nutrition support. Sauna therapy may have assisted with detoxifying their toxic exposure.