How Long Should You Sauna To Boost The Immune System?

In this blog post, I talk about how long you should use a sauna to boost the immune system. This blog post is part of a series on the health benefits of infrared saunas. There I’ve considered how long you should use a sauna for different purposes, such as heart health or joint problems.

Today the specialisation is the human immune system. I’ve written several detailed blog posts on saunas and the immune system in the past, such as:

• How Infrared Saunas Improve A Natural Immunity
• The Incredible Infrared Sauna Immune System Boost
• How To Use A Sauna For A Cold
• Is A Sauna Good For COVID?
• Sauna COVID Risk
• How Infrared Saunas Support Lymphatic System Detoxification
• Infrared Sauna Benefits For Lupus: An Unexpected Story
• Is A Dry Sauna Good For Pneumonia?
• Why An Infrared Sauna For Pneumonia Is Your Best Option

Today I’ll touch on many of these topics but from a very different perspective: the optimal time to spend inside a sauna. Lots of research has investigated the benefits of sauans for the immune system and uses specific protocols that have proven results. I’ll explore that research today.

How Long Should You Sauna For The Immune System

Depending on your goal, you should sauna for different periods of time for boosting the immune system. For instance, if you want to increase white blood cell count - the basic cell of the immune system - then a 15-minute sauna session is already good enough.

If you want to prevent respiratory disease in general though. For respiratory diseases in general and disease such as pneumonia or COVID in particular, it’s best to build up to four weekly sauna sessions per week. These effects are exclusively preventive so once you get ill I don’t recommend using a sauna at all. 

Make sure to build up to four weekly sauna sessions slowly over time though. And if you’ve got a chronic health condition, consult your physician first before engaging in intense sauna sessions.

Want to know all the details? Then keep reading the full blog post on the sauna and immune system benefits:

Infrared Sauna Immune System Benefits: Are Infrared Saunas Good For The Immune System?

In this section I’ll tell you how saunas aid the immune system in working more effectively and efficiently. But before I can do that, let’s first consider some immune system basics:

Immune System Basics

The immune system in biology - especially the human one - is ingenious. That immune system has many working parts but at the very core it can be subdivided into two main parts that interact: the innate and adaptive immune systems (1; 2; 3; 4; 5; 6; 7). 

That immune system doesn’t stand alone but interacts with your day and night cycle (circadian biology), your gut microbiome, the food you eat, your brain, and so forth. The immune system also interacts with the outside world constantly and it learns from these interactions. You might even say that the immune system thinks of its own because it draws lessons from previous invaders.

At the most basic level, the role of the immune system is to distinguish between the self and the non-self. Bacteria, viruses, or allergens need to be distinguished by that immune system from your own cells. Often, that goes correctly. 

And when that invader is strong enough, you might get sick temporarily until the invaders are overcome. As a result, the adaptive immune system creates a memory of that invader so that it can be swiftly death with in the future. 

Sometimes, however, the immune system also draws incorrect conclusions. In that case it falsely accuses your own cells to be invaders - so it incorrectly identifies the “self” as “non-self”. This incorrect conclusion then results in pathologies such as Multiple Sclerosis, Psoriasis, Lupus, and so forth.

So next up, let’s explore how saunas aid immune function at the fundamental level:

Saunas And The Immediate Immune Response

Fortunately, multiple studies exist that examine the effects of saunas on the immune system (8; 9). A 15-minute sauna sessions already boosts the immune response. After that session, there was an increase in white blood cells in the immune system. White blood cells - also called “leukocytes” - are the most basic type of cell of the immune system. 

After those 15 minutes of sauna, different types of white blood cells increased in quantity. These are basophils, lymphocytes, and neutrophils. All these immune cells play a different role in the immune system. Noteworthy was that athletes saw the biggest increase in their white blood cells compared to non-athletes.

In the long-run, additional immune system benefits exist. Over time, the immune response to saunas is extremely complex, with many different cells and moving parts either inhibited or stimulated. 

Instead of talking about the very complex specifics of these moving parts within the immune system, I’d rather focus on outcome for different diseases. I do want to explore one aspect of saunas and the immune system further though - the so-called “heat shock proteins”:

Sauna, Heat Shock Proteins, And Immunity

Saunas have a huge effect on the “heat shock proteins” in your body (10; 11; 12; 13; 14; 15; 16; 17; 18: 19). Many animal and human studies show this effect. Heat shock proteins are like a thermostat in your body that senses both low and high temperatures. That thermostat can then sound the alarm bell and initiate a cascade of physiological reactions to protect your body against overheating or undercooling.

As a temporary stressor, those heat shock proteins have massive effects on your overall health. Activating these heat shock proteins regularly has benefits for countering heart problems, diabetes, dementia and Alzheimer’s, and other diseases. However, the heat shock proteins also have significant effects on the immune system.

In turn, heat shock proteins also have huge effects on the immune response (20; 21; 22; 23; 24). Activating heat shock proteins can activate immune cells such as lymphocytes and macrophages. Also, levels of messenger cells in the immune system called “cytokines” can be changed through the heat shock proteins. 

And, heat shock proteins may play a role in autoimmunity or the protection agains them. More direct research is needed in humans between the link of heat shock proteins and autoimmune diseases but currently, theoretical projections assume the likelihood is high that there’s a link between them. The same is true for cancer - there’s a promising likely link but more research needs to be carried out here (25; 26; 27: 28).

Whole Body Hyperthermia, Inflammation, And The Immune System

As you already know, hyperthermia - or “overheating” - has an effect on the immune system. And that’s especially true for a protocol called “whole body hyperthermia”. In the whole body hyperthermia protocol, your body is heated to the maximum extent in a 40-90 minute period while your head is cooled. That protocol has large consequences for the immune system as well (29; 30; 31; 32).

The biggest takeaway so far is that a single 15-minute session in a hot regular sauna or an infrared sauna is sufficient to boost your immune system. Over time, these changes also accumulate. So even after a 10-week period of three weekly sauna sessions, the heating of your body continues to affect the immune system.

Let’s move on to the next topic:

How Saunas Help Boost The Immune System Against Common Pathologies Such As The Flu Or COVID

Below I’ll consider the effects saunas have on different pathologies. Not only do I consider the common cold but also COVID, a few autoimmune conditions, and more:

Does A Sauna Help Against The Common Cold And The Flu Viruses?

Currently, there’s evidence that spending time frequently inside a sauna prevents a common cold. But, once you have a cold, sauna time doesn’t make it go away quicker (33; 34; 35; 36; 37).

Several studies have looked at whether sauna time improves the course of a common cold and there’s no evidence for benefit. There might be slight benefit of spending time inside the sauna for nasal congestion though - so countering one of the most frequent symptoms of common cold.

Nevertheless, what I really recommend is not engaging in intensive sauna sessions if you’re sick from a cold. With a mild cold it’s still okay to do a mild, non-intensive sauna session. But if you’re really sick from a cold or from the flu, it’s highly recommended not to engage in intensive sauna sessions. Doing so can set you back and ensure you take longer to recover.

For a cold, preferably use an infrared sauna for 15 minutes to clear the nose. Don’t stay in longer because you might make recovery worse.

Next up:

Should You Use A Sauna For A Fever? What Are Potential Side-Effects Of Using A Sauna In These Cases

No human studies have been carried out directly on using a sauna for the flu. Having a fever is a sign that your body is fighting hard and that its immune system is really active at that moment. The reason of temperature increase is that it helps you body defend better against invaders (38; 39; 40).

A high grade fever raises your temperature as high as 40 degrees Celsius. That’s as high as you can go with a sauna as well, but if you’re at 40 degrees temperature at room temperature, adding more heat is dangerous.

The solution? Wait until your fever is gone and you’re back at a 37-degree body temperature. Then slowly start your sauna routine again and monitor how you’re doing to ensure you’re recovering well.

Can A Sauna Give You A Cold?

No, a sauna cannot give you a cold (41; 42: 43). However, it is possible to contract a cold in a sauna for two reasons. 

First, if there’s a person who is infected with the common cold, they’re more likely to spread that virus to you. And as saunas are enclosed spaces, spreading the virus becomes much easier. Secondly, if you’re already getting sick, don’t put lots of pressure on your body with intense sauna sessions as you’ll likely make things worse.

So what can you do when you’ve got a common cold? First, just rest. And secondly, when you feel a cold coming up, just take some zinc longenzes under your tongue and increase your vitamin C dose. Citrus fruit or a common vitamin C supplement are excellent vitamin C sources.

Does A Sauna Help With COVID-19?

You and I are in great luck as many studies have investigated the effects of saunas on COVID-19 (44; 45; 46; 47; 48; 49). In this case too, spending time inside a sauna is mostly protective and preventive and doesn’t fix a coronavirus infection once you’re sick.

If you feel you’re getting sick but aren’t sick yet, there might be a slight benefit from turning up the heat and stimulating your immune system. The reason here is that the effect of spending time inside a sauna mimics a fewer and stimulates the immune defence. 

Overall though, in studies in the Finnish population, a higher fitness level and more frequent sauna visits are very protective against COVID-19. Overall, when comparing two sauna sessions per week or more to people who use the sauna only once, total pneumonia risk goes down with 19%. And, as there’s a slight overlap between pneumonia and COVID-19, scientists speculate that a higher weekly sauna frequency is also protective against COVID-19.

Another benefit here is that heat is very damaging to the coronavirus causing COVID-19. The risk is thus extremely low that you’ll contract COVID-19 inside a hot sauna. 

For the best results, ensure you’re spending at least 30 minutes per day, twice weekly, inside an infrared sauna. If you develop good fitness of your heart and respiratory system, risk goes even down further. You can accomplish that goal by engaging in 30 minutes of exercise before your sauna session - but talk to your physician if you’ve got chronic health conditions first.

Does A Sauna Help With Respiratory Diseases Such As Pneumonia?

Just as with COVID, you and I are very fortunate that there’s ample of fascinating scientific evidence on saunas and respiratory diseases (50; 51; 52; 53; 54). As always, good results can only be obtained as preventive measures, not as therapy if you’ve got an acute respiratory illness.

Now here’s the great news:

The more of a sauna routine you build, the better you are protected against respiratory diseases. Respiratory diseases pertain to your airways in general – not exclusively your lungs. 

When comparing people who use the sauna once weekly, those who use the sauna twice or three times per week see a 27% reduction in airway disease. For four sauna sessions per week or more, that risk goes down by a whopping 41%. Both acute and chronic airway disease were prevented with a regular sauna routine.

And for pneumonia, as stated earlier in this blog post, the risk goes down by 19% if you’re using the sauna twice per week or more. A high fitness level - meaning you frequently challenge your heart, circulatory, and respiratory system - is additionally protective there.

Overall, chronic inflammation levels also go down the more frequently you use a sauna. In cases of heavy inflammation, which can play a role in pneumonia, spending time more frequently inside a sauna is additionally protective.

Some studies even show a pneumonia risk reduction of as much as 47% when you compare those with one weekly sauna session or less to those with four or more (54). These risk reductions are tremendous and would immediately be patented if a pharmaceutical company found a therapy that’s that impactful.

Moving on:

Does A Sauna Help With Nasal Congestion?

Lots of indirect evidence exists that raising the temperature in your nasal pathways helps open them up (55; 56; 57; 58; 59).

Fortunately, some studies also show that far infrared light can specifically help. Steam inhalation also works well. So, by proxy, it’s very likely that no matter what method you use, whether far infrared saunas, a Finnish sauna, or a steam room, it’s going to impede stuffiness of the nose.

I do want to be clear though that I’m talking about a single symptom here, a stuffy nose. Alternatively, you may have allergic rhinitis, commonly known as hay fever, that’s also more or less a localised phenomenon. I’m not talking about having a stuffy nose when you’ve got pneumonia or the flu - in those cases stay away from the sauna until you’re recovered. But in isolated cases of nasal congestion, it’s highly recommended to use an infrared sauna.

Also, if you want to upgrade your sauna’s ability to clear your nose, I recommend checkout out salt therapy. Salt therapy basically is purified salt (NaCl) that’s aerosolised into the air and enters your airways (60; 61; 62). The salty air - just as if you were spending time by the ocean - cleans your airways and provides minerals directly to your bloodstream.

We offer the HaloOne™ Salt Therapy that can be used inside any infrared sauna. You can use that salt therapy at the same time you’ve got your infrared sauna session so you basically double your benefits. How it works? Simple: You put a salt pod in, press a button, and you get results. 

Does A Sauna Help You Deal With Allergies?

Except for the studies I’ve quoted earlier on allergic rhinitis, no studies have investigated the effects of saunas on allergies. So if you’ve got a peanut allergy or an allergy against milk proteins, no research currently exist on those topics. However, due to anecdotal evidence, it’s also extremely unlikely that people with these health conditions have benefits as they would have reported it in the past.

For allergic rhinitis or hay fever, clearing the airways is the main benefit of infrared saunas and traditional saunas.

Does A Sauna Help With Autoimmune Conditions?

Saunas will help in some cases of autoimmune conditions but in most there’s no evidence for help. For instance, I wrote a long blog post about using infrared saunas with Lupus. In that blog post, I made the case that infrared saunas can help you at several levels. 

First, infrared saunas help your body increase its energy production and blood circulation, which are two problems associated with Lupus. Secondly, infrared saunas help you deal with (chronic) pain. And thirdly, you’ve got a safe way to expose yourself to infrared light if you cannot tolerate any sunlight anymore because of the Lupus without triggering yourself.

Whether saunas are beneficial or harmful for other autoimmune diseases lies beyond the scope of the argument of this blog post. If you’ve got an autoimmune condition, such as Multiple Sclerosis, diabetes type I, or rheumatoid arthritis, start very slow and observe your effects. Talk to your physician first though, before ever starting.

Often, there’s simply not enough scientific data to make a good scientific judgment. For instance, only one study exists on Multiple Sclerosis and saunas right now (63). For diabetes type I, some evidence exists for benefit - making insulin injections more effective, for instance (64; 65). And for rheumatoid arthritis, the results are actually extremely promising (66; 67; 68).

Moving on to another very important topic:

Red Light Therapy And Near Infrared Light For The Immune System. A Secret Immune System Tool For Infrared Saunas?

There’s one extremely important topic I haven’t considered before in this blog post. That topic is the use of red and near infrared light inside a sauna. All our Clearlight^® Saunas can be equipped with a Red Light Therapy Tower or full-spectrum heaters. The former emits both red and near infrared light and the latter near and middle infrared. 

I’ll consider the red and near infrared specifically here and their relation to the immune system. By adding full-spectrum heaters or a Red Light Therapy Tower to your infrared sauna you’ll get the following benefits:

• Potential counteraction and prevention of autoimmune issues (69; 70; 71; 72). Rheumatoid arthritis and thyroid problems are two examples thereof.
• Lowering lung and airway inflammation (73; 74; 75; 76; 77). Problems due to asthma or dust mites are examples here. The red and near infrared light likely also help with COVID-19.
• Reduces excessive inflammation (78; 79; 80; 81; 82; 83). Excess inflammation is related to a dysfunctional immune system as well as many chronic diseases if the inflammation is also chronic. 
• Counters acute and chronic pain, which is a very common symptom of people who have immune issues (84; 85; 86; 87; 88; 89).
• Increases energy-production (90; 91; 92; 93). Current scientific consensus holds that red light therapy increases so-called “Adenosine Triphosphate” (ATP) production in your cells. That ATP is a currency that can then be spent on goals such as improving your immune system functioning.

Many other benefits exist as well that I won’t go into here. Suffice it to say that you can upgrade the sauna for immune system benefits with some very impressive benefits of red and near infrared light.

Lastly, there’s a very important question many people have regarding the best sauna for the immune system:

What Is The Best Sauna For Boosting Immunity? Traditional Versus Infrared Saunas

Let me be clear: the scientific evidence for both traditional and infrared saunas is great for boosting the immune system. However, if you’d had to pick one option then infrared saunas are the better choice. Several reasons exist for this finding:

First, infrared saunas make you feel very relaxed and offer an extremely gentle experience. You’re not exposed to very hot air as the infrared light or heat warms you up from the inside out. Hence, you’ll still sweat hard and get results are in a more comfortable position. For instance, you don’t have to breathe in very hot air in an infrared sauna. Especially for immune system problems that gentle infrared sauna experience is very important.

Secondly, with a quality infrared sauna, only the correct tissues are heated up. You’re not heating up your head directly - the weakest link in the body when it comes to sauna time. And when you don’t heat up your head and only your core, arms and legs, you can last a lot longer with a gentler experience. As a result, you’ll sweat more and have better results. 

So overall, I consider the infrared sauna the best sauna for boosting the immune system.

Side-Effects: What If You Feel Sick Or Weak After A Sauna?

Although side-effects after a sauna are rare, they can happen. In such a case, make sure you’re hydrated well and get some rest. 

Sauna sessions shouldn’t make you feel worn down extremely. If you do regularly get worn down by a sauna session, then the temperature of the sauna is too high (or the infrared heat too intense), or you’re staying inside the sauna for too long. Too frequent sessions can also cause problems. 

Monitoring how you’re doing during a sauna session is especially important if you’re sick or if you’ve got an immune system condition such as autoimmunity. Always consult your physician before using a sauna regularly with a (chronic) health condition.