How Infrared Saunas Work: The Science Behind Infrared Heat

Ever since its existence, heat therapy has been a revolutionary wellness practice, and then in the 1960’s, it evolved into something much more than the traditional Finnish sauna.

Infrared saunas have gotten increasingly popular amongst athletes, wellness enthusiasts, and people looking for a more comfortable alternative to traditional saunas. But for those who don’t know the science behind how infrared saunas work, the question is, are they actually worth it?

Conventional saunas heat the air around you. Infrared saunas use light energy to warm your body directly. This means that an infrared sauna can function at lower temperatures, around 45–65°C, while delivering the deep warmth and sweating you’d expect from a sauna. 

But what does this all mean?

In this guide, we will learn more about how infrared saunas work, explore their benefits and drawbacks, learn how to use them effectively and safely, and finally, understand if they are worth the hype.

Quick Answer: How Do Infrared Saunas Work?

The technology behind infrared saunas uses infrared light to heat the body directly rather than exposing the body to a hot environment. This works better because infrared energy gets absorbed by the skin and underlying tissues. It will then raise the body’s temperature and simulate blood circulation and sweating, triggering heat-therapy physiological responses. 

Since infrared energy does not heat up the air around you in the sauna, you can enjoy longer sessions while still effectively experiencing the benefits of heat therapy, like relaxation, recovery, and cardiovascular stimulation.

What Is an Infrared Sauna — The Simple Definition

So we know that what happens in an infrared sauna is the infrared light heating up our body directly instead of heating the surrounding air. The word “radiation” can seem intimidating, but infrared radiation is simply a form of energy that already exists alongside visible light, so, nothing dangerous.

Think of it this way: being in a traditional sauna is like being in a very hot room (literally). Being in an infrared sauna is more like standing in direct sunlight. Even if the air around you is not hot, you still feel the radiant heat that warms your body.

Because of the way this radiation system works, infrared saunas can operate at lower temperatures, typically between 45 to 65°C. This is the temperature comparison between different types of heat therapy rooms:

• Infrared Sauna: 45–65°C 

• Dry (Finnish) Sauna: 80–100°C 

• Steam Room: Lower temperatures combined with high humidity.

Let’s get a bit technical. Infrared saunas use specialised heaters that produce infrared wavelengths. There are 3 types of infrared wavelengths: near infrared (NIR), mid infrared (MIR), and far infrared (FIR).  Far infrared is the wavelength used in infrared saunas because it’s the longest wavelength, meaning it produces a more gentle and broad warming effect without making the air unbearably hot. 

Is an Infrared Sauna Actually Good for You? 5 Bulletproof Evidences 

Understanding how infrared saunas work does not stop with the technology; It’s also about what this type of heat therapy does for your physical and mental health. We’re not talking about “Saunas detox your body through excessive sweating” type of benefits. We’re talking about scientific evidence of how infrared sauna sessions improve your overall well-being:

Cardiovascular Health

One of the most researched benefits of infrared saunas relates to heart health. How infrared saunas work in favour of our cardiovascular health? By improving blood circulation. When your body is heated up, your blood vessels will start widening in a process called vasodilation. When this happens, blood flows and moves more easily throughout your body, improving your heart’s overall health. Your heart rate will also increase in the heat, which creates a similar response to a light-to-moderate cardio exercise.  

Recovery, Pain Relief, and Physical Performance

Another great benefit of improved blood circulation in an infrared sauna is post-exercise recovery. Better blood flow means more oxygen flow to your muscles, which helps reduce feelings of stiffness and encourages relaxation after training.

Regular infrared sauna sessions have also helped many people with chronic pain conditions, like arthritis and fibromyalgia. Results vary between individuals, but regular infrared sauna sessions can help reduce discomfort and improve overall well-being.

Stress Reduction and Nervous System Recovery

One of the most important benefits of an infrared sauna has actually little to do with sweating. Direct infrared heat exposure can relax your nervous system. When you are stressed, your nervous system enters a fight-or-flight state. What infrared heat does is shift your body out of this state and more towards a rest-and-digest state. That’s why people feel calmer, more relaxed, and overall, more mentally refreshed after a session. Regular infrared sauna sessions can help you slow down and recover from the modern daily stress.

Skin Health

We are, again, going back to blood circulation. Improved blood circulation means more blood flow to the skin, which has shown improvement in skin issues like acne, eczema, and psoriasis. The scientific evidence in this area is still developing, and it’s still early to decide that this is a proven fact, but the findings are extremely encouraging!

Immune Function

Heat exposure raises your core body temperature. One interesting fact is that this temperature rise stimulated certain immune responses, like increased activity of white blood cells. Now, this doesn’t mean that infrared saunas can cure your cold or other immune system-related diseases; it means that regular heat exposure can help improve your overall immune system function.

So to answer the ultimate question here, yes, infrared saunas are good for you. The benefits of infrared saunas all show improvement in cardiovascular health, recovery, relaxation, and stress management. There are still so many studies researching the benefits of infrared saunas, and the growing body of evidence proves that infrared sauna use can be a great wellness tool when practiced safely and consistently.

Disadvantages of Infrared Sauna — The Drawbacks

Infrared saunas are beneficial, but they don’t do magic. Unfortunately, many companies trying to sell saunas publish false claims as part of their marketing and sales plan. In order for you to enjoy the benefits of infrared saunas safely and without any risks, we are going to go through the true disadvantages of infrared saunas.

Dehydration

When it comes to saunas, first matter of concern is always hydration. Infrared sauna sessions can cause extreme sweating. While this is a normal thing, it also means your body is losing fluids and electrolytes. To avoid dehydration, always hydrate before, during, and after an infrared sauna session, but be careful not to drink ice-cold water.

Overheating

Overheating is another drawback to consider. Due to how infrared saunas work, if you do long sessions or set the temperature too high, you might experience overheating. If, at any point in your session, you start feeling dizzy, lightheaded, or unwell, leave the sauna immediately and cool down. Again, to cool down, never drink cold water. You can take a shower or just sit in a room-temperature area.

Detoxification

Let’s get back to what we discussed earlier about false claims. Many people promoting sauna use usually claim benefits that are not backed by research and data. Benefits like cardiovascular health, recovery, and everything we mentioned earlier are being researched and proven by different studies. But claims like “detoxification” are not yet well-supported by peer-reviewed evidence. Before starting your heat therapy journey, research well to avoid being sold unrealistic benefits.

Cost and Convenience

Cost and convenience are other factors when it comes to infrared saunas. Like any other wellness tool, saunas also cost time and money. If you don’t have a sauna cabin in your house, you’re faced with a gym or spa membership, plus travel costs. But, if you wish to have an indoor or outdoor infrared sauna at the comfort of your home, head over to Polar Recovery’s infrared sauna page, where we offer a well-curated set of infrared saunas to match your exact requirements and space.

Weight Loss

Possibly the worst way to market infrared saunas is by saying heat therapy causes weight loss by “breaking fat up.” How infrared saunas work towards your well-being is by supporting recovery and improving blood circulation. Any weight loss that you may experience during a sauna session is primarily the weight of the water your body has lost. You will regain that weight typically once you rehydrate. So, just bear in mind that sauna use is not a replacement for regular exercise.

Now that you know how infrared saunas work, their benefits, and their disadvantages, let’s get into more practical information. How do we actually use an infrared sauna?

How Long Should You Stay in an Infrared Sauna?

There’s a lot of speculation about exactly how long you are supposed to be in an infrared sauna to get the results and benefits without overheating. The ideal session varies from person to person based on experience level, goals, and heat tolerance. But there is a general rule about session length you can use, especially if you are new to using infrared saunas:

As an important rule, remember that sessions longer than 60 minutes are not recommended because of the risk of dehydration and overheating.

How Often Can You Use an Infrared Sauna?

Now that we know our session duration rules, another query pops up: consistency. You have noticed that we have talked about getting the most out of infrared saunas by being consistent, but how often is actually consistent?

• If you are a beginner, start with 2–3 sessions per week, so your body can slowly and gradually adjust to heat exposure.

• For most healthy adults, given they stay hydrated and tolerate the heat well, 4–7 sessions per week is ideal to get the benefits of heat therapy.

• Once you build up your heat tolerance, you can use infrared saunas daily, but keep your sessions between 15–30 minutes.

Interesting infrared sauna use fact: many studies suggest that consistency matters more than occasional long sessions for achieving the ultimate benefits of heat therapy. 

Who Should Avoid Infrared Saunas?

Okay, we know how infrared saunas work and also how often and how long we are supposed to use them. Next important question is, can everybody use it? To answer this question, you need to know that on some occasions, you need to completely avoid not just infrared saunas, but heat therapy, or seek medical advice before use.

Infrared sauna use is generally not recommended if:

• You are pregnant

• You have a pacemaker or certain implanted medical devices

• You have a bleeding disorder

• You have an active fever or infection

• You have a diagnosed condition that affects your body’s ability to regulate heat

Speak to a healthcare professional before using an infrared sauna if you have:

• Cardiovascular disease or an irregular heartbeat

• High or low blood pressure

• Multiple Sclerosis (MS)

• Diabetes with neuropathy

• Parkinson’s disease

One factor to consider is that some medications can affect the body’s response to heat. If you take these medications, you need to talk to your healthcare advisor before using a sauna. Some of these medications are diuretics, antihistamines, beta-blockers, and certain blood pressure medications.

Also, please remember that alcohol and sauna do not mix well. Sauna sessions increase the risk of dehydration, which is a terrible combination with alcohol consumption.

Infrared Sauna vs Traditional Sauna — Which One’s Better?

Infrared saunas and traditional saunas are both heat exposure methods with the same goals and benefits. However, they work differently:

Traditional saunas have a stronger long-term research base, since they have been around longer than infrared saunas. However, infrared saunas offer the same heat therapy benefits at lower temperatures. This means that people who prefer a more comfortable sauna use, or cannot tolerate the dry heat of traditional saunas, can also benefit from heat therapy with infrared saunas.

How to use an Infrared Sauna — Before, During, and After

There are some recommendations on what to do before, during, and after using an infrared sauna to ensure your experience is safe, comfortable, and effective:

Before Your Session

• Drink 1 or 2 glasses of water at room temperature before entering the sauna

• Avoid heavy meals within 1–2 hours of your session

• Remove metal jewellery; They can heat up during your session

• Avoid alcohol before your sauna session

During Your Session

• Set the temperature between 45–65°C, and at the lower end if you are new

• Bring water into the sauna to stay hydrated

• Find a comfortable position, like sitting or lying down, to allow heat to build up gradually

• Leave the sauna immediately if you feel dizzy, nauseous, or unwell

After Your Session

• Allow your body temperature to stabilise for 5–10 minutes

• Rehydrate with room temperature water or electrolyte drinks

• Note if you wish to shower: warm water for relaxation, cool water for a refreshing effect

• Again, if you wish to shower, wait for 20–40 minutes before showering to allow seating to naturally subside. If you wish to shower immediately, avoid cool water.

Final Verdict — Are Infrared Saunas Actually Worth the Hype?

Yes. That’s the whole point this guide proves. Infrared saunas are a useful and more accessible form of heat therapy, offering all of the sauna health benefits to users who want a comfortable sauna experience. While some benefit claims about how infrared saunas work still need further research, especially on detox and skin health, the overall evidence is encouraging. They are, of course, not a miracle solution, but they provide a practical and comfortable way to support your general well-being. 

Frequently Asked Questions

Are infrared saunas actually good for you?

While results vary between individuals, there’s a good amount of evidence showing that infrared saunas are beneficial for circulation, relaxation, cardiovascular health, and post-exercise recovery when used consistently.

Are saunas good for high cortisol levels?

Saunas generally support relaxation and help your body’s nervous system regulate better, which can influence stress regulation. 

What do 30 minutes in a sauna do to your body?

30 minutes in a sauna increases heart rate, improves circulation, triggers heavy sweating, and promotes muscle relaxation.

Are saunas ok for people with MS?

People with MS should consult their healthcare provider before using saunas. This is because heat can temporarily worsen symptoms.