That’s why we wanted to shine light on some studies and research that are exploring how heat and infrared can help people feel better from the debilitating and vitality-robbing effects of depression.
Editor's Note: Updated October 2021 with the newest study by Dr. Ashley Mason and Dr. Charles Raison on the "Feasibility and acceptability of Whole-body hyperthermia (WBH) protocol" published recently in the International Journal of Hyperthermia. It offers exciting hope for people with major depressive disorder and sets the stage for more study using far infrared sauna domes for WBH, starting soon. We are excited to keep you posted on this important ongoing work.
A group of researchers, whose mentor fondly refers to as the “heat advocates,” are passionate about finding alternative treatments. The group includes experts at four universities across the country. Ideally, they dream of finding treatments that are “fast-acting, safe, and convenient to obtain. The successful development of these therapies will require a better understanding of the mechanisms of depression and how to directly target them.”1
They all connected because their independent investigations converged in the results of a study by Dr. Charles Raison, published in the Journal of the American Medical Association Psychiatry in 2016.2 The findings of that study piqued their hope and interest in the possibilities of hyperthermia (elevating core body temperature) to unlock options to relieve symptoms: “Whole-body hyperthermia holds promise as a safe, rapid-acting, antidepressant modality with a prolonged therapeutic effect.”
Raison’s randomized, double-blind study investigated a foundational fact discovered in a 1982 study3 that noted one simple point: patients with depression had temperature dysregulation, an inability to cool themselves down, especially at night. When depression symptoms decreased, so did body temps. At the time, no one understood the significance, which spurred researchers to conduct an exploratory study in 1996. They did one simple test of a theory that hyperthermia (heating the body to mimic a core body “fever” temperature) may play a role in relieving depression symptoms.
Raison expanded on that in 2016, when his research team looked at 30 participants diagnosed with major depression. They assessed the effects of one session of whole-body hyperthermia (“WBH”) on symptoms compared to a placebo group. WBH is a medically-supervised therapy using intense infrared heat (close to 200°F (93.3°C)) to elevate core body temp to activate the body’s natural stress response. The WBH session raised participants’ core body temperature to a mild hyperthermic temp of 101.3°F (38.5°C) and compared results to participants who received a treatment like WBH without the intense heat. The results? Significant reduced symptoms were observed within 1 week and lasting for the 6-week follow-up period; an outcome researchers found exciting and worth exploring more.
Raison’s passion is finding the underlying causes of depression. He’s a pioneer seeking an integrated theory of everything on the origins of depression. He’s the author of The New Mind-Body Science of Depression and his term, “Pathogen Host Defense Theory of Depression” (“PATHOS-D”) integrates emerging understandings of underlying mechanisms of depression, centering on the idea that there’s a possible evolution-based protective immune response that activates inflammation in the body.4
That’s a ground-breaking, game-changing idea.
Raison’s work is focused on that area of study, and he’s passing the heat-connection torch on to the other heat advocates. All of them share common hope and desires for finding alternative “nonpharmacological” treatments. Raison encourages and supports their work and has cultivated their connection.
- Chronic inflammation is associated with depression and may be a protective, inflammatory response involving thermoregulatory pathways, the immune system, serotonin system, heat shock proteins and more.5,10
- Exercise is known to help depression. Can the passive cardio and anti-inflammatory benefits of heat help with depression as well?6
- How does the practice of hot yoga affect depression symptoms?7
- What does sweat reveal about body temperature dysregulation and depression, as many people experience excessive sweating as a side effect of SSRI antidepressant medication?
- Sleep and heart disease are integrally connected to depression. Can heat be a key help with multiple issues?
- Neural signals coming from heating skin may play a role in stimulating specific areas of the brain.
- What role does ambient heat vs infrared waves play in raising effective core body temperature and relieving symptoms of depression?
- Can commercially-available infrared saunas offer an effective and desirable treatment?8,9
- What can biomarkers tell us about what’s going on in the body during depression and application of heat for treatment?9
The results of Raison’s 2016 study caught the eye of Dr. Ashley Mason, one of his former graduate advisees and now an integrative psychiatrist who directs the Sleep, Eating and Affect (SEA) Lab at University of California San Francisco Osher Center. She got excited because SSRI antidepressants can take weeks or months before they start to work. Dr. Raison saw effect a few days after only one session.11
Mason wanted to figure out how to use heat in a scientifically feasible way that would also be more accessible. Using a WBH device presented challenges and limitations:
- Expensive device (appx. $50,000)
- Very uncomfortable heat that many people may not be able to endure for longer periods
- Not very accessible and can be difficult to obtain (made in Germany)
WBH is an emerging field and while WBH and sauna both involve heat, they are very different experiences.
Saunas have been around for years and offer pleasurable, relaxing, calming experiences that leave you feeling better. You are free to get in and out and enjoy the experience.
WBH is an emerging field used with specific, controlled protocols requiring you to stay in a very, very hot, intense experience for an hour or more. It is a treatment, not a spa-like experience.
Using a commercially-available and affordable personal infrared sauna dome provided a viable option for the next study.
"Feasibility and acceptability of a Whole-Body hyperthermia (WBH) protocol"
Dr. Mason has taken the lead in the follow-up on Raison’s WBH research. Her most recently completed clinical trial involving 25 people cleared the way for the next study to test personal far infrared sauna domes as safe WBH treatment for physically healthy people with depression and was published October 2021.8
The 2019-2020 interventional study used a far infrared sauna dome heated to appx 135°F for up to 110 minutes to achieve core body temp of 101.3°F, with the participant's head outside the sauna. The protocol administrator provides water and cold cloths to keep the patient comfortable. Other studies found depression symptoms are reduced more when people spent more time getting to the peak temperature. So in the protocol, Dr. Mason started the treatment cooler, and allowed the participant to heat up with the sauna, which the study found helped people endure the treatment better.
The safety study concluded "this novel WBH protocol holds promise in further assessing the utility of WBH in MDD (major depressive disorder) treatment."
“HypErthermia as an Additional Treatment for the Biology & Experience of Depression (HEAT BED) Study"
Dr. Mason used the first trial to design protocols to test in her next two planned clinical trials over the next 3 years that she hopes will pave the way to proving heat treatment as a real, clinically-valid treatment for depression. The protocols involve WBH sessions combined with proven cognitive behavioral therapy for depression (“CBT-I”), the “gold standard” first-line treatment for depression with a therapist.
The idea came from the 2016 study when researchers noticed study patients often started chatting, which is uncharacteristic of depression’s social withdrawal symptoms. They theorized that if WBH increased people’s desire to talk more, then pairing sauna’s traditional communal social experience may cause people to engage more in the therapy. The trial will test a dual intervention with a mind and a body component.
She’ll also be gathering some of the first biological data to hopefully learn more about the underpinnings of depression, and how sauna sessions may affect people with depression at a molecular level.
If Mason’s theories prove correct, the future could hold bright promise for treatment of depression.
- Capitalizing on sauna benefits may help people participate in WBH therapy. Treatment doesn’t work if people won’t do it. Sauna use could be a pleasant, desirable option that helps patients get over that hurdle.
- Lifestyle factors influence depression, and exercise improves depressive symptoms. It’s not easy to get someone who is depressed to exercise. Sauna mimics moderate cardio exercise and could help people with depression, or who have injuries or other problems, to get a form of exercise.
- Cardiovascular disease and depression often go hand in hand. There is a large group of people struggling with both for whom sauna may have a positive effect for both conditions.
- Would people rather take drugs that have side effects or sit in a sauna where they can read a magazine while they get treatment?
These studies are exciting next steps toward discoveries that may bring hope and healing for millions suffering from depression.