October 14, 2021
15 min read

Red Light Therapy And Near Infrared Red Light Therapy

Does Red Light Therapy Work And How?

Most people think of light as something that only allows for visibility of their direct environment. (Sun)light, for instance, allows you to see what’s going on around you. And at nighttime, the absence of light makes your environment invisible.

Sounds simple, right?

For health, however, there’s more to the story:

In fact, the light in your environment directly affects your health. Sufficient levels of light exposure, in fact, is essential for the human body!


That statement sounds really abstract so allow me to explain:

For millions of years, sunlight was the main light source in the human environment. Those brightness-providing sun rays actually penetrate the skin's surface. In other words, light can thus directly venture into your body to affect chemical processes therein1;2.

Get our free eBook

8 tips to get the most out of your Infrared Sauna

Discover proven ways to supercharge your infrared sauna experience.

By downloading the eBook, you agree to subscribe to the Clearlight newsletter. Unsubscribe at any time.

Today, many people spend most of their time indoors - artificial light bulbs have become the main source of light exposure for humans.

To understand why that difference matters, let’s dig a bit deeper into what “light” is:

From a physics perspective, light is made up of “wavelengths”. Some of those wavelengths of light - such as infrared - warm the body from within. As a result, you’ll get feelings of a greater sense of well-being, have more energy, and perform better.

When you’re outside, the wavelengths emitted by the sun provide you with that feeling. If you’re indoors all the time, you won’t get sufficient light exposure, and unfortunately, won’t reap those benefits

Let’s consider why that matters:

The sun emits several different wavelengths. To be more precise, the sun emits 1) visible (all the colors of the rainbow); 2) infrared (IR) and; 3) ultraviolet (UV) wavelengths or light.

And you know what’s really interesting?

You absorb those wavelengths through photoreceptors located in the skin. Your body also converts the light into energy3. That process works similarly to the well-known metabolic progress “photosynthesis”4. In photosynthesis, plants use light to convert carbon dioxide into oxygen. Photosynthesis is essential for all plant life on earth.

In your cells, that process is essentially reversed!

Let’s explore that relationship between light and your body a bit further:

Without going into too much detail, the energy-producing processes in your cells are also affected by light in your environment. That basic process of light absorption by photoreceptors brings many fundamental health benefits.

Clearlight Saunas Australia & New Zealand supplier of Jacuzzi® Saunas offers saunas that use infrared wavelengths to heat you up from the inside. In this article, however, I will not cover that specific topic.

Instead, I’ll break down the latest studies around “red and infrared light therapy” in this blog post in simple to understand terms. I’ll also talk about the benefits of this therapy and I consider some commonly-asked questions.

Contrary to using an infrared sauna, red and infrared light therapy barely heats your body up, but it does provide your body light that penetrates deep into your tissues.

Let’s explore that statement some more:

Red and infrared light therapy” contains to two primary forms of light:

  1. Red light.
  2. Near infrared light, which is a small piece of the infrared (IR) spectrum.

Here´s a deeper explanation of the wavelengths used in red and infrared light therapy:

  • First, red light is made up of wavelengths between ~ 620 and 780 nanometers in length.
  • Secondly, near infrared light wavelengths are found between 780 and 1,400 nanometers.
  • Lastly, wavelengths above 1,000 - which heat your body up - are not used in red and infrared light therapy - so we won’t discuss those in this article. In other words, only infrared between 780 and 1,000 nanometers is commonly used.

(If you’re not a physics geek then there’s no need to remember those numbers)

This red and infrared light therapy I’m talking about is also frequently described with other names, such as “Low Level Laser Therapy (short: LLLT)”, “LED light therapy”, “photobiomodulation”, and “red light therapy”.

(To keep things simple, I’ll go with the name “red light therapy” in this article)

So let’s consider why red light therapy is so different from anything else on the market today:

History Of Red Light Therapy

In this section I’ll dig deeper into the basics of red light therapy and how it developed:

Red light therapy has been used for decades, although, mostly through lasers. Consumer red light therapy, on the other hand, has only been used extensively for about a decade.

Consumer red light therapy almost exclusively uses LED lights, instead of lasers, which are much safer to apply5. When you’re using LEDs, there’s (almost) no risk of damaging any tissues, except for under the most extreme circumstances.

The red light therapy sold by Clearlight Saunas Australia & New Zealand supplier of Jacuzzi® Saunas exclusively uses those side-effect friendly LEDs.

So let’s consider why LEDs are used in the first place:

Contrary to infrared saunas, red light therapy functions almost exclusively based on light and has a very low heat component. In other words, an infrared sauna heats you up from the inside while red light therapy provides you with light that penetrates deep into your body.

In northern Europe, the classic incandescent heat lamps have traditionally been very popular. These bulbs are mainly used for sinusitis or muscular tension.

Whilst these incandescent heat bulbs also produce small amounts of red and near infrared light, these lamps have nowhere near the same benefits and intensity as their red light therapy counterpart6.

Fortunately, the red light therapy industry in Australia, as well as its applications, have grown exponentially in the last few years. New panels that emit new wavelengths and different treatment protocols hit the market every single week.

What’s amazing is that red light therapy has been very extensively researched in thousands of studies. When the correct treatment parameters are used in these studies, about 85% of these thousands of studies show positive results7.

Due to these promising scientific findings, red light therapy quickly established itself among athletes and Olympic participants the last few years. Natural health clinics and healing centres have also integrated this form of therapy for accelerated recovery to assist their wide range of patients and customers.

Red light therapy has, in fact, taken the health industry by storm. Michael Hamblin, a Harvard University professor, thinks that within a decade, most homes will have a red light therapy device.8

This snippet explores the history of the scientific research conducted on Red Light Therapy.

Let’s then explore that “next big thing” some more.

How Does Red Light Therapy Work?

Remember that thanks to photoreceptors in the human body, your skin naturally absorbs and metabolizes the incoming light (a.k.a. radiation).

Not all light is created equal though. All these wavelengths or rays of light have a different effect or are absorbed differently by the skin.

One classic example is the effect of sunlight on the skin, which, among other things, ensures that the human body can produce vitamin D9. Part of the ultraviolet light spectrum initiates the physiological creation process of vitamin D.

In red light therapy, two specific ranges of light wavelengths complement with each other, which, when used together, cause the effect of “photobiomodulation”.

Let’s break down that term “photobiomodulation”. In latin, “photo” stands for “light”, “bio” denotes “biology”, and “modulation” signifies “change”. “Photobiomodulation” thus means “light modulation biology” or, simpler: “light changing life”

Phrased differently, the term “photobiomodulation” describes the metabolism of light energy into electrochemical energy in the human body.

Put in more plain terms, light that enters your body influences the chemical and electrical processes in your body10. Every single biological process in your body depends on chemistry and electricity (and their interaction).

Or, even simpler: light energizes your body.

As a result, the effects of this supplied energy are versatile.

If you would like to learn more about how red light therapy works, click here.

This snippet speaks on how Red Light Therapy works.

What Does Red Light Therapy Do?

Let's look at the biological effects.

For the effect of photobiomodulation to occur, you require two specific wavelength ranges which I’ve talked about earlier:

  1. red light in the visible range of 600-670 nanometres (nm)
  2. near infrared light in the range of 800-860 nanometers (nm)

The merging of these two parts of that light spectrum, at a sufficient intensity, guarantees the process of photobiomodulation is effective. Only using the right parameter will thus result in the desired health benefits.

In other words, if the light output of a panel is very low, you won’t get much if any benefit. Moreover, many wavelengths do not guarantee the desired effect, which is why classic red light lamps do not promote the same health outcomes.



If you were to use the 710 nm wavelength, you won’t get the same benefits as you would by using 630 nm or 810 nm11.


Well, one mechanism of certain wavelengths of light is that they activate biological processes in your cell’s “mitochondria”. Scientists consider those mitochondria the “the power plants of your cells”.

Mitochondria have a variety of functions in the cells, in particular they are responsible for the production of adenosine triphosphate (ATP). ATP acts as an energy store in the cells and thus, fuels the body. Within a very short time after exposure to the correct wavelengths, the mitochondria upgrade their power station function and produce more fuel as ATP.

The increased ATP production, in turn, leads to more energy in the cells and subsequently the body.

(Alternative theories about the cell’s energy-generation exist that I won’t go into here)12

The bottom line is this: you need the right red light therapy panel with the correct wavelengths and a high light output.

Curious yet?

Let’s then take a look at what health benefits you can expect from this therapy.

Benefits Of Red Light Therapy

The list of health benefits is impressively long and will examine them individually below.

In summary, it can be deduced above all that increased cell health or increased cell frequency is an ideal prerequisite for many processes that support a healthy body and mind!

That dynamic is often compromised by stress in everyday life, chronic fatigue, insufficient nutrition and insufficient movement/exercise. All these consequences can also lead to the weakening of the immune system.

At the cellular level, the cell function is reduced and the human body has less energy for vital processes.

For instance, these negative factors lead to an increase in a compound called “nitric oxide” (NO). This increase may be harmful when nitric oxide binds the enzyme cytochrome C-oxidase (CCO).

Without overcomplicating too much, “COO” is part of the energy-creation process in the cell and needed for cell health. Adding red light therapy will break down the bonds between NO and CCO, therefore increasing overall cell health.

(Phrased differently: COO compromises one necessary step of the energy-creation process in the mitochondria - COO is highly dependent on red and infrared light as an input to function optimally)13.

This snippet explains some of the health benefits associated with Red Light Therapy.

How Many Red Light Therapy Sessions Do You Need?

Optimizing the results of your red light therapy sessions can come down to what you expect from your sessions.

Some users experience relief from their individual problems right after the first application. As a rule, however, lasting improvement requires continuous and correctly-applied exposure.

So, just like healthy eating is a habit you should follow for the rest of your life if you want to reap its benefits, the same is true for red light therapy.

Let’s dig deeper into the details:

After the near-infrared and red light device has been installed in the desired location and switched on, the following usage guidelines must be observed:

How To Use Red Light Therapy Devices

This snippet explains the different ways to correctly use your Red Light Therapy devices.

1. The skin must be directly exposed to the light without barriers whenever possible.

You should thus avoid wearing everyday clothes, make-up and glasses. Thin underwear is allowed, although the best results are obtained when you are completely naked. Even contact lenses should be removed temporarily.

As long as you do not look directly at the LEDs for a long time, the near-infrared light has a positive effect on the area around the eyes, which is why experts believe that special protective glasses are not necessary.

2. You can carry out red light therapy in either a sitting or standing position.

The decisive factor is rather that you keep the prescribed distance to your device. In general, you can assume a distance of about 5-10 cm for optimal effect. For this, it is essential that you observe the specifications of your device.

If you stand away too far from the device, the power density will be lower and you won’t get optimal results. Simply put, the LEDs need to be close to the skin for optimal penetration into your body (The higher the dose on your skin, the deeper the penetration, so the better deeper tissues such as bones, blood vessels, muscles, and organs benefit).

3. For beginners we recommend a slow familiarization period at the beginning. Start with relaxed one- or two-minute treatments and increase to a usage time of 10 to 15 minutes within the next two to three weeks.

(If you’ve got a (chronic) health condition, this step is especially important.)

Also, if you’ve got any problem areas on your body, such as painful joints, you might want to treat these areas individually first, before progressing to full body treatments.

(If you’re using a big panel, you can cover up the areas you don’t want to treat yet with clothes to lower exposure)

Also, this familiarization period allows you to cut back on your sessions to an exposure level that has worked well in the past, if you ever begin to experience symptoms such as fatigue or increased joint pain.

4. Over time, building up to an average of one daily session is great. Most people use red light therapy 4-5 times a week, and experience the greatest benefit with that habit.

If you miss a day or have to do without your red light therapy due to important appointments, this is completely okay. However, you should not skip more than two or three days a week, otherwise your results will be inconsistent or sub-par.

With LED light therapy it is very similar to fitness training: you will experience the best results with consistent exposure over time.

5. My recommendation is to find the time of day that suits you and your everyday life. With red light therapy after getting up you can start the day with new energy or provide recovery directly after a training session in the afternoon.

Even at night, the treatment can be beneficial and provide an alternative to bright, artificial light. With nighttime exposure, it’s best to experiment though, as some people find red light therapy too stimulating just before bedtime.

Want even more recommendations for your sessions? Keep reading the section below - you’ll get access to a few more insights:

Recommendations from Clearlight Saunas Australia & New Zealand supplier of Jacuzzi® Saunas:

Need more info? Here are some Frequently Asked Questions (FAQs):

1. How Long, How Often Should I Use Red Light Therapy For Results?

Everyone is different, and accordingly it is difficult to give a concrete answer to this question. However, based on our analysis of the market and the studies I’ve cited before, the following is recommended:

Ideally 1x per day for 10-12 minutes at a distance of 5-10cm. If the distance is greater (e.g. 15 cm), the duration of use should be doubled, i.e. approximately 20 minutes. I recommend daily use, especially in the beginning, so that the photoreceptors in the skin get used to this form of light application.

More than once a day is not useful because the cells in the irradiated region cannot absorb more energy through this form of light. So, just like with exercise, more is not necessarily better.

2. In What Body Positions (e.g. Standing & Laying Down) Can I Use Clearlight’s Red Light Therapy?

Due to the product design, the ARL Mini and ARL Plus+ can be used very flexibly. A suspension is included in the scope of delivery, which makes it possible to hang the red light therapy on a hook or on the door. Furthermore, the product can be used standing or lying down.

Other possibilities could be to use it while meditating in the morning or while reading.

It is important that there is as much bare skin as possible so that the photoreceptors can absorb the light.

Lastly, only the Clearlight Red Light Version can be safely used within the Clearlight Infrared Cabins®. Red light therapy panels from other brands will almost certainly not withstand the heat buildup in our infrared cabins, leading to quick defects.

4. What is the level of EMF and ELF exposure when using Red Light Therapy?

Due to the very low power consumption, the exposure to electromagnetic frequencies is negligible. Unlike an infrared cabin, where many currents run around the body due to the presence of radiant heaters, magnetic fields, electric fields, and dirty electricity remain very close to the panel itself even though levels are already very low.

So, with red light therapy you have a much lower exposure to electromagnetic and electric fields. Due to the distance of approx. 5-10 cm, the exposure is basically negligible.

5. Do any Safety Concerns or Potential Side Effects Exist When Using Clearlight Red Light Therapy?

Clearlight's team of experts takes potential risks to our customers very seriously. Rest assured that negative side effects and consequences associated with infrared cabins and technologies are minimal and potential problems are eliminated thanks to extensive research in the field and high grand materials.

This guarantee of safety has been a key reason for Clearlight's founders to invest in light therapy from the very beginning.

In the worst case scenario, you can expect the usual side effects of a sauna session associated with the increased temperatures. Healing processes demand something from the body, which may result in symptoms such as headaches or exhaustion if used excessively.

In contrast to sunlight, however, red light therapy lacks wavelengths such as UV rays.

Additionally, our cabins protect you from the harmful effects of sunburn. However, the cabins cannot guarantee a tan due to that precise absence of UV light.

And because the infrared panels do not emit ultraviolet-B, which helps your skin create vitamin D, you therefore still have to obtain vitamin D from other sources.

Should you nevertheless experience any complaints or have specific questions regarding your near infrared red light therapy, do not hesitate to contact a health care professional and notify us immediately.

But just to fully inform you, let’s consider a more exhaustive list of potential side-effects:

While exceedingly rare, the following 5 side-effects can result from red light therapy in some very specific circumstances:

1. In some people, red light therapy can cause temporary fatigue. That fatigue is completely harmless and will subside after a good night's sleep.

The reason for that effect is a process called “hormesis”. Hormesis signifies the body’s adaptation to some temporary stressors. These temporary stressors not only include exercise and cold exposure but also light therapy, specifically the wavelengths used in red light therapy!

If you’ve got chronic fatigue, or another health condition, you might want to start more slowly with your sessions. If not, you might temporarily feel more fatigued, as if you’ve just completed an intense workout!

2. Using red light therapy over areas with carcinogenic tissues has not been fully scientifically understood yet.

And, because we don’t have certainty regarding red light therapy on cancer tissues yet, for now, I always recommend covering up such areas for now.

Again, I don’t imply there will be (potential) harm, I just want to be safe rather than sorry!

3. Red light therapy uses LEDs, which “flicker”. Flicker means that lights turn on and off many times a second, which causes issues in some people.

Even though most people’s eyes and brains are affected in minute ways due to flicker of light bulbs - such as fluorescent and LED bulbs - for some, side-effects are more prevalent.

If you can sit in a room with fluorescent and LED bulbs activated, then there’s no need to worry about this specific side-effect. Again, I’m just mentioning this potential side-effect to provide you with all information you could possibly need.

4. In many people, using red light therapy before bedtime reduces their melatonin levels and therefore sleep quality.

In others, however, using red light therapy before going to sleep helps them sleep more deeply.

Simply put, if red light therapy before bedtime reduces your sleep quality, then use it during the morning, afternoon, and perhaps even early evening.

5. Although mostly theoretical in nature, red light therapy could have slightly different effects than sunlight exposure over time.

Why? Red light therapy exposes your body to very specific wavelengths such as 660nm and 810nm, which maximally affect mitochondrial function. Sunlight, on the contrary, includes some wavelengths, such as 760nm, which inhibit mitochondrial energy production, on the contrary.

This side-effect has not been investigated by science and, due to the positive experience of millions of people, it’s extremely unlikely that a harmful effect will be found.

Again, as you can see, side-effects can theoretically occur, but are only present in a few exceedingly rare scenarios.

And that’s it - an overview of the history, physiological effects, and benefits of red light therapy. Let’s zoom out, consider the 30,000-foot view, and conclude:

Conclusion: Welcome To The Red Light Therapy Revolution!

Every now and then breakthroughs exist in science & technology that are truly beneficial to humanity. For instance, car travel not only transformed human transportation but society as a whole.

Red light therapy - and light therapy more broadly - might be understood in the same way in the decades to come. Since the Industrial Revolution, you, I, and our fellow human beings have progressively moved indoors. And by living indoors, however, we disconnected from the healing powers of the sun.

Fortunately, part of that light spectrum emitted by the sun, the red and infrared portion, is now accessible at your fingertips with red light therapy. I, Johannes Kettelhodt, am truly excited with these developments. Let me explain why:

A few decades ago, infrared saunas gave tens if not hundreds of millions of people an unmatched ability to detoxify, feel great, and relax. Clearlight improved upon that trend and supplies you with the highest-quality infrared saunas sold today.

Right now, in the same way, red light therapy provides you with faster recovery from sports, improved well-being, enhanced hormonal health, better skin quality, an uptick in cognition, and far more! And once again, Clearlight decides to contribute to this trend.

Join us in bringing your health to the next level! Why? 

Because you deserve the very best.

If you're interested in an infrared sauna cabin for home, click here to view our range of full-spectrum saunas, far-infrared saunas, and outdoor saunas.

Clearlight would like to remind users that this should not be taken as direct medical advice, and you should always consult a licensed health practitioner before making any significant changes to your lifestyle or existing pain treatment regimen.

Red Light Therapy Evidence

1. R J Wurtman. The effects of light on the human body. Sci Am. 1975 Jul;233(1):69-77.

2. Michael F Holick Biological

3. Michael A Crawford, C Leigh Broadhurst, ... Walter F Schmidt. A quantum theory for the irreplaceable role of docosahexaenoic acid in neural cell signalling throughout evolution. Prostaglandins Leukot Essent Fatty Acids. 2013 Jan;88(1):5-13. doi: 10.1016/j.plefa.2012.08.005. Epub 2012 Nov 30.

4. O-M H Richter, B Ludwig. Cytochrome c oxidase--structure, function, and physiology of a redox-driven molecular machine. Rev Physiol Biochem Pharmacol. 2003;147:47-74. doi: 10.1007/s10254-003-0006-0. Epub 2003 Feb 21.

5. Vladimir Heiskanen, Michael R Hamblin. Photobiomodulation: lasers vs. light emitting diodes?. Photochem Photobiol Sci. 2018 Aug 8;17(8):1003-1017. doi: 10.1039/c8pp90049c.

6. Hoon Chung, Tianhong Dai, ... Hamblin M. The Nuts and Bolts of Low-level Laser (Light) Therapy. Ann Biomed Eng. 2012 Feb; 40(2): 516–533.

7. Vladimir Heiskanen, Photobiomodulation (PBM) / Low level laser therapy (LLLT) / red/NIR phototherapy studies - a comprehensive database, internet resource:

8. Michael Hamblin. Shining light on the head: Photobiomodulation for brain disorders. BBA Clin. 2016 Dec; 6: 113–124.

9. D J Turnbull 1, A V Parisi, M G Kimlin. Vitamin D effective ultraviolet wavelengths due to scattering in shade. J Steroid Biochem Mol Biol. 2005 Sep;96(5):431-6.

10. Juanita Mathews, Michael Levin. The body electric 2.0: recent advances in developmental bioelectricity for regenerative and synthetic bioengineering. Curr Opin Biotechnol. 2018 Aug;52:134-144. doi: 10.1016/j.copbio.2018.03.008. Epub 2018 Apr 21.

  •    •    •  

Request Pricing

* Mandatory fields