Saunas and Mental Health Improvement

Saunas and Depression

When the body heats up, the brain responds by altering its chemical balance. A sauna triggers the release of serotonin – a neurotransmitter associated with feelings of pleasure and calm – and lowers cortisol levels, the primary stress hormone.

In addition to serotonin, heat stimulates the production of beta-endorphins and activates the raphe nuclei of the brainstem – the very same neural pathways targeted by SSRI antidepressants, but through a different biological mechanism.

Japanese researchers have documented this state at the level of brain activity. In the state of "totonou" – a unique sensation of deep calm and clarity following a sauna – an electroencephalogram records an increase in theta and alpha waves, which correspond to a relaxed yet focused state of consciousness. At the same time, levels of stress markers in saliva decrease.

UCSF researchers conducted a pilot study in which patients with major depressive disorder received four sessions of infrared sauna therapy alongside cognitive-behavioral therapy. The results were clinically significant: of the 12 participants who completed the protocol, 11 no longer met the criteria for depressive disorder after treatment.

The mechanism proposed by the researchers: people with depression typically have elevated body temperature, and the sauna triggers prolonged cooling of the body after the session, which may be therapeutic specifically for this group.

Clinical reviews confirm the general trend. Studies of patients with chronic fatigue syndrome have shown that 4-8 weeks of regular infrared sauna sessions significantly improve scores on depression and anxiety scales compared to control groups.

It is important to understand, however, that a sauna cannot replace psychotherapy or medication. It is a supportive tool. Therefore, if you have symptoms of depression, the first step should be to consult a specialist.

Anxiety and Stress

After leaving the sauna, heart rate gradually slows, muscles relax, and cortisol levels drop: this is how the parasympathetic nervous system takes precedence over the sympathetic nervous system. The body shifts from «fight or flight» mode to «rest and recover» mode.

A study on women showed that a 20-minute session at 80°C significantly increased alertness and reduced tension, depression, anger, fatigue, and cognitive confusion. At excessive temperatures (120°C), the effect was the opposite. So, as they say, «too much of a good thing is bad for you».

Saunas and more serious disorders

One of the most striking findings concerns more severe mental disorders. A Finnish prospective study that followed over 2,000 men for nearly 25 years found that those who visited the sauna 4-7 times a week had a 77% lower risk of developing psychotic disorders compared to those who went once a week (I guess, it is hard to find a «No sauna» control group in Finland!).

A 2024 study confirmed that even after accounting for physical fitness levels, frequent sauna use remained an independent protective factor against psychosis.

A plausible explanation is that the sauna reduces chronic activity of the hypothalamic-pituitary-adrenal axis – the very system whose excessive activity is a precursor to psychotic symptoms. In addition, group sauna visits reduce feelings of social isolation, which is one of the risk factors for psychosis.

Improvement of pain symptoms

Mental state is closely linked to physical well-being. Saunas reduce the manifestations of chronic pain (such as in fibromyalgia) that accompany depressive states. By alleviating physical pain, saunas help break the vicious cycle of emotional dysregulation and improve mood.

The Sauna as «Social Cure»

And, of course, the sense of community. It’s no coincidence that Finns love going to public saunas, even though almost everyone has their own at home. Saunas are used as a way to relax with colleagues and spend time with friends. Visiting the sauna together creates a strong social therapeutic effect. According to the «Social Medicine» psychological model, a sense of belonging to a community and social interaction during group sauna sessions significantly improve psychological well-being and reduce feelings of loneliness. The shared ritual experience promotes so-called emotional synchronization among participants, thereby increasing positive emotions and sharply reducing negative states. It also provides an opportunity to build friendships. So, invite your friends over!