How Saunas & Heat Therapy Improve Mood and Sleep

Patrick Frank
Oct 26
6 min read

Updated: 5 days ago

Imagine a wellness solution as simple as sitting in a heated room. What if the path to better mood, deeper sleep, and even improved mental health was as accessible as embracing heat? This transformative concept is no longer mere speculation—groundbreaking research is uncovering how saunas, heat therapy, and whole-body hyperthermia could play pivotal roles in holistic well-being.

Dr. Ashley Mason, a psychologist and researcher at UC San Francisco, is at the forefront of this exploration. In this article, we delve into her findings and the potential of heat therapy to enhance mental and physical health, all while promoting detoxification and longevity. Whether you’re a fitness enthusiast, a mindfulness practitioner, or someone curious about natural wellness solutions, this comprehensive look at heat-related therapies offers actionable insights tailored to your well-being goals.

The Power of Heat Therapy for Mental Health

Core Body Temperature and Its Connection to Mental Health

One of Dr. Mason’s standout observations reveals a link between core body temperature and depression. People with clinical depression often exhibit higher core body temperatures and smaller fluctuations in their circadian temperature rhythms. Healthy individuals typically experience a pronounced drop in body temperature at night, followed by a daytime rise—this fluctuation is called circadian temperature amplitude. However, in individuals with depression, this amplitude is diminished, and their bodies remain warmer than usual, even at night.

Intriguingly, studies show that when people with depression recover, their body temperature drops, and their circadian temperature amplitude increases. While these changes in temperature are slight—measured in decimals—they are consistent across diverse populations, suggesting a critical relationship between thermoregulation and emotional well-being.

Why Does Heat Therapy Work for Depression?

Heat therapy, particularly whole-body hyperthermia, involves raising the body’s internal temperature to mimic a mild fever. Dr. Mason’s lab uses infrared heating devices to achieve this, keeping participants’ heads cool while their bodies heat up. This therapy has shown promising results in reducing symptoms of depression, even in combination with cognitive behavioral therapy (CBT). In one study, 91% of participants who completed a 10-week program combining heat therapy and CBT no longer met clinical criteria for depression.

Unlike medications that primarily target brain chemistry, heat therapy appears to work by stimulating the body’s natural cooling mechanisms. This may lead to an overall decrease in core temperature—a process that correlates with reduced depressive symptoms. This opens exciting possibilities for non-pharmaceutical interventions, especially for those who prefer natural or complementary treatments.

Saunas and Sleep: How Heat Prepares the Body for Rest

Struggling to fall asleep? Saunas and other heat therapies might hold the key. Falling asleep requires a drop in core body temperature, and heat exposure can jumpstart this process. By raising your body temperature during a sauna session or a warm bath, you activate sweat-induced cooling mechanisms that continue even after you leave the heat. This post-sauna temperature drop can help people with sleep-onset insomnia—those who find it difficult to fall asleep—by fostering the conditions needed for restful sleep.

Dr. Mason is currently studying infrared heating blankets as part of a combined treatment for insomnia. Participants use the blanket for a set period before bedtime, which accelerates the cooling process and prepares the body for sleep. Preliminary results suggest that people find the treatment pleasant and are more likely to adhere to it, making it a promising tool for improving sleep in the comfort of one’s home.

Detoxification and Sweating: Does Heat Therapy Remove Toxins?

The idea that sweating helps the body detoxify from harmful chemicals like "forever chemicals" (PFAS) and microplastics is compelling, but the science is still evolving. Sweat’s primary purpose is to cool the body, and while studies have detected heavy metals and other toxicants in sweat, it remains unclear whether this represents meaningful detoxification or just trace levels.

Dr. Mason’s lab is actively exploring this question with a study involving firefighters, a group heavily exposed to environmental toxicants. By analyzing blood, sweat, and urine before and after heat treatments, the research aims to determine whether toxicants are excreted in significant amounts. While the findings are not yet conclusive, the potential benefits of heat therapy for occupational detoxification are undeniable.

Beyond Depression: The Broad Health Benefits of Saunas

The benefits of saunas extend far beyond mental health, touching nearly every facet of physical well-being. Longitudinal studies from Finland, where saunas are a cultural mainstay, have shown that regular sauna use is associated with:

Lower risk of cardiovascular events like strokes and heart attacks.
Reduced rates of dementia and Alzheimer’s disease.
Improved arterial flexibility and blood flow.
Decreased hypertension risk.

These benefits are not limited to traditional Finnish saunas. Infrared saunas, hot tubs, and even hot yoga classes can offer similar physiological effects. However, Dr. Mason emphasizes that sauna use should complement—not replace—exercise. Combining both activities amplifies the health impacts, providing a one-two punch for longevity and vitality.

Traditional vs. Infrared Saunas: Which Is Best?

Traditional saunas heat the air around you, often through hot rocks and added steam, while infrared saunas use radiant heat to warm the body directly. Infrared saunas are less intense in terms of air temperature but may not heat the body’s core as effectively as traditional saunas. Both options have their benefits, so the best choice will depend on personal preference and goals.

For those who value social interaction, traditional saunas offer a communal experience. Infrared saunas, on the other hand, are often quieter and more private, making them ideal for solo relaxation. Dr. Mason advises trying various options to see which fits your lifestyle before investing in a home setup.

Practical Advice for Sauna Use

If you’re new to saunas or heat therapy, here’s how to get started:

Frequency Matters: Aim for 2-4 sessions per week to maximize health benefits. Studies suggest that 4-7 sessions yield the greatest impact.
Duration: Stay in the sauna for as long as it feels comfortable, typically between 15-30 minutes per session. Avoid overexertion or dehydration.
Hydration: Drink water before and after your session to replenish fluids lost through sweating.
Timing: Experiment with sauna use at different times of day. Some find it relaxing before bed, while others prefer mornings to jumpstart their day.
Listen to Your Body: Exit the sauna if you feel dizzy, overly hot, or unwell. Moderation is key.

For those interested in home use, consider the type of sauna that aligns with your preferences—whether it’s a traditional Finnish setup or a compact infrared device. Evaluate factors like installation costs, available space, and maintenance needs to make an informed decision.

Key Takeaways

Mental Health Boost: Heat therapy, particularly whole-body hyperthermia, shows promise as a complementary treatment for depression, enhancing mood by promoting thermoregulation.
Sleep Support: Saunas or warm baths can help alleviate sleep-onset insomnia by accelerating the body’s cooling mechanism.
Longevity and Heart Health: Regular sauna use is linked to reduced risk of cardiovascular events, improved arterial flexibility, and enhanced overall health span.
Customizable Experience: Whether you prefer traditional saunas, infrared options, or hot tubs, choose the method that aligns with your lifestyle and preferences to ensure consistency.
Exercise Synergy: Saunas complement—not replace—exercise, making them an excellent addition to a holistic wellness routine.
Detox Potential: While promising, more research is needed to confirm whether sweating meaningfully eliminates toxicants like PFAS and microplastics.
Ease Into It: Start with shorter sessions and lower heat settings, gradually increasing as your body adapts.

Conclusion

Heat therapy is more than just a relaxing ritual—it’s a scientifically supported tool for improving mental health, sleep, and physical resilience. Whether you’re sitting in a Finnish sauna, using an infrared heating blanket, or soaking in a hot tub, the key is consistency and enjoyment. As Dr. Mason aptly puts it, "Find the heat treatment that you love and stick with it." By doing so, you’ll not only enhance your well-being but also nurture your body’s ability to heal, recover, and thrive.

Embrace the power of heat. Your mind, body, and spirit will thank you.

Source: "Why you need to get Hot to feel better | Dr. Ashley Mason" - Viva Longevity!, YouTube, Sep 14, 2025 - https://www.youtube.com/watch?v=dU4vYZ4tFV8