Infrared saunas are heating up in popularity as more and more people are discovering their sizzling health benefits. Unlike traditional saunas, which heat the air around you, infrared saunas heat your body directly using infrared rays. This infrared heating produces a deeper, more rejuvenating sweat and a steaming dose of health benefits for the mind and body.
In this article, I’ll look at the science behind infrared light, using heat therapy for health, and the latest scientific studies about what infrared sauna benefits you can expect from an infrared sauna. So read on if you’re ready to feel the heat in all the right ways.
- Deliberate Heat Exposure / Thermotherapy?
- How Does Infrared Sauna Work?
- Infrared Sauna Benefits
- Benefit #1: Improves heart health
- Benefit #2: Reduces chronic pain and tiredness
- Benefit #3: Promotes longevity
- Benefit #4: Boosts growth hormone
- Benefit #5: Boosts Metabolism
- Benefit #6: Improved athletic performance
- Benefits #7: Better mood and mental health
- Benefit #8: Reduces cortisol and stress
- Benefit #9: Deeper and better sleep
- Benefit #10: Strengthens the immune system
- Infrared Sauna FAQ
Deliberate Heat Exposure / Thermotherapy?
Deliberate heat exposure, or thermotherapy, uses heat to raise your body’s temperature and improve your physical and mental health.
Using heat for health is nothing new; sauna has a long history worldwide as a way to relax and heal the body. Public bathhouses were a pastime of the ancient Romans, used by everyone from politicians to recovering gladiators. Finnish traditional saunas can be traced back as far as 700 BC when visitors believed they housed healing hot water spirits.
Putting aside Roman politics and magical Finnish spirits, there is something to be said about how cultures worldwide have understood the power of heat.
If you want a cheap way to do heat therapy and don’t mind a bit of cardio, you could run in heavy clothes or plastic bags, Rocky Balboa style! This method of heating up is a longstanding favorite of boxers.
But for most people, you’ll likely want to do one of the following:
- Dry e.g. heat pads, dry sauna
- Wet e.g. hot baths, steam rooms
- Infrared e.g. infrared sauna and sauna blankets
- Electrotherapy e.g. high frequency ultrasound
Mindset is a form of the placebo effect, where your thoughts about what you’re doing change how your body reacts to the thing you’re doing.
This concept is nicely demonstrated in the following study by Dr. Crum. In the study, researchers told one group of cleaners that their day-to-day work counted as intense exercise. This group was compared to another group of cleaners who were not told anything (the control group). The group that believed they were doing intense exercise lost weight, lost body fat, and lowered their blood pressure compared to the control group. Now that’s mind over matter.
To be clear, the mindset phenomenon does not mean that you can think your way to health benefits that an infrared sauna does not offer. Rather, it tells us there is a synergy between mind and body when you are informed and intentional with a health practice.
Infrared light is a type of light with a longer wavelength than visible light. This long wavelength is what makes infrared light invisible but also deeply penetrating.
But do not worry; infrared rays are safe and do not damage cells. In fact, much of the warmth you feel from sunlight is infrared light.
Not only that, you produce infrared heat yourself! If you want to test this out, hold your palms a few centimeters from your cheeks or forehead. After a few seconds, you should feel a warm glow on your face – this is your body’s natural infrared heat.
Infrared saunas emit three types of infrared light:
Far-band infrared is the most beneficial because it penetrates the deepest into the body, reaching the fat layer beneath the skin. Here, the light is absorbed and stimulates the production of heat. For this reason, infrared saunas are often said to provide “inside-out” heating.
Although the most effective type of infrared light is the Far-band, the addition of near- and mid-band infrared light can enhance potential health benefits. A sauna that uses all three types of infrared light is termed “full spectrum.”
Infrared saunas have heaters that emit infrared light. As I mentioned before, this light is absorbed and heats up the skin and deeper soft tissues.
Because of the deep “inside-out” heating effect of infrared saunas, they tend to use lower temperatures – typically between 65˚F (35°C) and 167˚F (75°C). Though this is not as hot as a dry or wet sauna, a lower temperature means you can enjoy longer sessions with less discomfort.
There are lots of choices when it comes to infrared saunas, so check out our best infrared sauna picks for more information.
Before we can get into the benefits of heat, we have to understand how it is that heat drives positive health effects in the body. It’s all thanks to hormesis.
Hormesis is a concept that describes how moderate doses of stress on the body, known as hormetic stressors, can result in positive health effects.
Just like a muscle grows in response to the stress of lifting heavy weights, so too do your body systems become tougher when exposed to heat stress.
With that said, you should take care the hormetic stress is not too much. If the hormetic stress is too great, your body will be unable to cope and is at risk of harm. Returning to the weightlifting analogy, it’s akin to attempting to lift a weight that’s too heavy. At best, you will fail and see no benefit. At worst, you risk injury.
This is why taking it slow and knowing your limits are essential. A good hormetic stressor should hit that sweet spot of stress. Not too little but not too much.
So take your time with the heat. Start at a challenging but manageable temperature, and increase over time.
Now that you generally understand how heat stimulates changes in the body let’s explore the science behind the various health benefits of heat and infrared saunas.
Whole-body heat therapies, such as infrared saunas, have been shown to improve heart health. This is because heat provides exercise-like stress to the heart.
Studies show that far-infrared sauna therapy can improve blood pressure and heart health. One notable study found that adding an infrared sauna to heart failure treatments improved the amount of exercise patients could do.
Another large study by the University of Eastern Finland showed that the more often people did sauna, the less likely they were to die of heart disease. The sauna sessions were between 176˚F (80°C) and 392˚F (100°C), and each sauna session lasted from five to twenty minutes. People who sauna bathed 2-3 times per week had a 27% lower risk of dying from heart conditions compared to people who did not use the sauna. This number shot up to 50% for people who used saunas 4-5 times per week. That’s an impressive result for just sitting in a hot room!
Evidence suggests that infrared sauna therapy can improve chronic pain and tiredness.
A meta-analysis of 42 studies found that infrared therapy reduced pain levels in people with long-term muscle and joint pains.
Another small study found that infrared sauna therapy can improve symptoms of chronic fatigue syndrome. Participants used did infrared sauna therapy five times per week for 15 minutes at a temperature of 140°F (60°C). At the end of the study, patients felt less tired and more able to do their daily activities.
Longevity is a field of science that tries to understand how people can live longer. Lucky for us, heat and sauna bathing positively affect longevity.
Sauna improves longevity thanks to the effect of heat on unique proteins called Heat Shock Proteins (HSPs). HSPs are made by your body in response to heat and protect your cells from heat damage.
One of these HSPs is called FOXO3. FOXO3 helps repair damaged DNA, resulting in longer lifespans for cells and tissues. This effect is so powerful that people with multiple FOXO3 genes are nearly 3 times more likely to live to 100 years or older.
Heat and infrared saunas can stimulate the release of different hormones. One hormone you should pay attention to is Human Growth Hormone (HGH).
HGH acts on nearly all tissues of your body. It stimulates cell repair, promotes organ healing, and shifts muscle into an anabolic (muscle-growth) state.
To put the power of HGH into perspective, HGH is the major driving factor behind those huge growth spurts in puberty. Unfortunately, HGH levels reduce after puberty and continue to fall as we age. But, this is where the sauna comes in.
One study measured the effects of a Finnish dry sauna on blood HGH levels. The protocol was 1 hour per day for 3 days in a single week, at a temperature of 176˚F (80°C). The study found a 16-fold increase in growth hormone levels. You read that right, 16-fold. That’s a whopping 1600% increase.
Although this study used Finnish dry saunas, heat from any sauna will cause HGH release as long as the temperature is sufficiently high. An infrared sauna is no exception.
Sauna has long been famous as a way to cut weight. Although many believe saunas can only help you cut water weight, studies suggest that saunas can also help you cut fat.
Previously I mentioned Heat Shock Proteins (HSPs) – proteins your body produces in response to heat stress. Two HSPs that are particularly relevant when talking about fat burning are HSF-1 and UCP-1.
HSF-1 causes the activation of beige and brown fat. Beige and brown fat are located around the spine, shoulders, and collar bones. These types of fat have many mitochondria, which means they consume a lot of energy compared to normal yellow fat.
UCP-1 increases the activity of mitochondria and is also known to help activate beige and brown fat.
The result of brown fat activation and increased mitochondrial activity is that you burn more fat and calories and increase your base metabolic rate. One study proved this mechanism, showing how HSF-1 increases with heating. The effect was so powerful that the researchers successfully treated obesity in mice with heating alone.
So don’t let anyone tell you that you can’t cut fat with an infrared sauna!
An ice bath should be your go-to for reducing muscle soreness and decreasing the recovery time between workouts. However, there is some evidence that using an infrared sauna during workouts can improve performance.
One small study looked at the recovery potential of infrared sauna bathing during a workout. Study participants performed a strength workout and then did a sauna session for 30 minutes at a temperature of 95-122 °F (35-50°C). People who did infrared sauna increased their countermovement jump compared to those who did no sauna.
The theory is that heat causes blood vessels to dilate and improves blood flow to the muscle. Increased blood flow can result in better recovery and performance during a workout.
People have long known that saunas improve mood and mental health. The theory is that heat triggers the release of feel-good endorphins. Endorphins are brain chemicals that make you feel happier, calmer, and less stressed.
The positive mental effects of sauna were apparent in one large randomized, double-blind study that found sauna reduced depressive symptoms significantly compared to placebo.
Another study examined the relationship between sauna use and the risk of developing schizophrenia. The study found that the more often someone used a sauna, the lower their risk of developing schizophrenia.
This data does not mean that the sauna alone can treat depression or prevent schizophrenia. But it shows that the sauna is an easy, healthy way to improve mood and can be used as an adjunct in treating mental health.
Cortisol is a hormone made by the adrenal glands in response to stress. Cortisol is the infamous “stress hormone,” and high cortisol levels are associated with chronic stress.
Chronic stress is unhealthy and is linked to a number of negative health effects, including weight gain, high blood pressure, and a weakened immune system. So it’s in your best interests to keep cortisol and stress low.
A recent study looked at the effects of sauna and cold water exposure on various hormones, including cortisol. The study participants did 12 minutes of a sauna at 192°F (90°C), followed by a 1-minute 50°F (10°C) cold water immersion. The study found that cortisol significantly reduced following repeated sauna and cold-plunge sessions.
More data is required to draw precise conclusions, but this presents a good baseline for showing how a sauna can reduce cortisol and stress. I recommend using the highest temperature possible on your infrared sauna to get similar results.
To understand why infrared saunas can produce better quality sleep, we have to discuss the effect of heat on our core temperature.
When you heat the body, its core temperature rises, and the hypothalamus kicks into action. Think of your hypothalamus as your body’s ‘smart meter’. When you heat your body and your temperature rises, the hypothalamus counteracts this by telling your body to lower its core temperature.
How does this relate to sleep? Well, your core temperature lowers at night. This cooler core temperature makes you feel drowsy and promotes deep sleep.
As well as that, a key to unlocking more rejuvenating sleep is maximizing slow-wave sleep. Slow-wave sleep is the deepest, most restorative phase of non-rapid eye movement (NREM) sleep and is vital for memory and learning.
One small study showed how using a sauna increases slow-wave sleep activity by 72%. Another study found that female athletes enjoyed better quality slow-wave and NREM sleep after a run in which they were heated, as compared to a run during which they were cooled.
So use your infrared sauna in the evening and enjoy a more restful sleep.
The exact mechanism behind this is unknown, but there is evidence that heating causes immune system activation.
One study found increases in infection-fighting white blood cells after using a Finnish sauna in people who already exercised regularly. Interestingly, people who did not exercise saw no increase in white blood cells after a sauna. Therefore it’s likely that exercise and sauna have a synergistic effect on your immune system.
Another study found that sauna bathing halved the number of common colds in a research group compared to a group that did not do sauna. This data shows that those increases in white blood cells may not be simply for show.
Some sources claim that the sauna triggers a fever-like state which helps fight off immunity; however, there is little evidence to say whether this is the case. Regardless, the data is promising enough to show how an infrared sauna could meaningfully enhance your immune system.
How Often Should You Use An Infrared Sauna?
The answer to this depends on what your goal is.
For most people, based on the studies discussed above, two to three 15-30 minute sessions of an infrared sauna should deliver most of the health benefits.
Suppose you want to use the sauna to achieve specific health benefits, e.g., increase your metabolism. In that case, I recommend following the protocol in the studies described.
The main risk with an infrared sauna is dehydration from sweating. To reduce this risk, hydrate before and after an infrared sauna session.
I recommend consulting with your healthcare provider before starting a new health practice. This is especially important if you:
• are pregnant
• have chronic health conditions e.g., heart, kidneys, etc
•have exposed areas of skin damage
Although many like pairing deliberate heat exposure with deliberate cold exposure, heating and cooling are very different. Your body is much more resistant to cooling than heating, and can only heat up so much before cells are damaged. So please proceed cautiously, especially if you are new to the sauna. Start at a low temperature and gradually increase the session time and/or temperature.
There are currently no known adverse health effects to using infrared light.
Remember, infrared light is non-ionizing. This means it does not damage DNA or cells.
How soon you see results will depend on what your goals are. For example, if your goal is to get better sleep, you could see results after your first session.
If your goals were to increase your metabolism or heart health, this might take weeks to months.
The main thing is to be patient and stay consistent with the infrared sauna; you’re sure to see benefits.
In conclusion, heat therapy using an infrared sauna is a powerful tool for improving our overall health and well-being. The benefits of infrared saunas include better performance, faster recovery, and reduced risk from physical and mental health diseases. Not forgetting, it can help you burn extra calories and tone up. So, don’t be afraid to crank up the heat and give your body the warmth it needs to thrive!