Red Light Therapy Benefits | Does it really work?
Written by Christopher Ioannou, BSc (Hons) Sports & Exercise Science
Reading Time: 10 minutes
Table of contents
The video version of this post:
In this post we are going to look at why light therapy has been utilised for thousands of years for its therapeutic effects. I am going to explain why red and near-infrared light in particular has received a whole lot of scientific attention in the past few decades, and how it’s now being used in specialised LED light panels to impart incredible health benefits.
Just a quick disclaimer. All the information provided is meant for educational purposes only. So please don’t use it to treat or diagnose any existing or pre-existing health conditions. Always consult your healthcare provider first.
With that out of the way, let’s begin.
What is Red Light Therapy?
Red light therapy, also known in the past as “low-level light therapy” and nowadays as “photobiomodulation”, has been researched for more than 50 years, and thousands of academic studies have proved it’s diverse range of therapeutic effects [1][4].
However, light or phototherapy using natural sunlight has actually been used for thousands of years. The ancient Egyptians called it “heliotherapy” [1].
Hippocrates, the famous ancient Greek physician, was known to prescribe frequent sunlight exposure to depressive patients. He believed that the Greeks were happier and more optimistic than the more northern European populations due to their higher exposure to light from the sun. And he was right!
Modern-day scientists have simply isolated the specific light frequencies that have healing properties – The red and near-infrared light used in photobiomodulation is just a band of therapeutic light frequencies within the broad spectrum of light that the sun emits. We can identify these frequencies most clearly at sunrise and sunset by the reddish colour of the sky at these times.
Later in this post I’ll explain the reason for which photobiomodulation researchers have isolated these frequencies and why companies are now producing LED powered red light therapy devices for home use, such as the ones in the images below.
Figure 1 - Home Use Red Light Devices
Now, to have a good grasp of light therapy, we need to first understand basic human energy production.
Let me explain.
Why Enhancing Mitochondrial Function is so Important
All living things require energy to survive. In the human body, this energy is in the form of adenosine triphosphate, or ATP for short.
Adenosine triphosphate, or ATP, is a complex organic chemical that provides energy to drive many processes in living cells. It is produced in the mitochondria, which are the energy units of cells.
We can stimulate the body to produce more mitochondria through regular physical exercise and subsequently have more potential energy at our disposal at any given time.
And the more mitochondria we have, the more energy we can produce.
This is why elite athletes have been found to have a greater density of mitochondria in their muscle tissue than the average person. This adaptation happens because of the energy demands they place on their bodies day in and day out, resulting in their bodies producing more mitochondria.
This is one of the major metabolic benefits of exercise and why it is promoted across the board in the health and medical fields.
However, this adaptation takes a long time and a lot of dedication on our part.
So, is there any other way for the body to make more energy that doesn’t require so much hard work?
Well, fortunately there is. Instead of trying to produce more and more mitochondria by exercising day and night, we could also make sure that the mitochondria we have already are functioning optimally.
This is where red and near-infrared light comes into the picture.
How Red Light Therapy Energises the Body by increasing ATP production
Newton’s law of the conservation of energy states that "energy cannot be created nor destroyed, but can only change its form."
We know that this is true for solar energy, whereby light energy from the sun is absorbed by solar panels to produce electrical energy. We also know that sunlight is transformed into energy by plants in the process of photosynthesis.
Well, it turns out that human cells are pretty similar in this regard. This is because when our cells absorb light energy, it sparks off a chemical reaction in the mitochondria to produce more ATP, which is our useable form of energy [5][6].
So again, in the same way that solar energy can be converted into electrical energy, so can light energy be used by our cells to produce more ATP.
Great, so what makes red and near-infrared light in particular so special then?
Why Red And NIR Light Is So Well Absorbed By The Body
Well, red and near-infrared light has a light frequency range of 600-1100 nm [5].
It just so happens that these frequencies transmit really well through our body tissues and into cells. So, whereas other light frequency lengths, such as blue light, fall short and can only enter into the first layer of the skin, red and especially near-infrared light can penetrate through all the layers of the skin and reach into our organs and even into bones, where they can activate our cells to produce ATP, as explained earlier.
Figure 2 - Blue, Red and Near Infrared Light Penetration Depths
Dr Michael Hamblin, the leading researcher on red light therapy, who has over 400 published papers to his name, explained this quite practically in an interview once. He said, “Take out your torch and shine it under a finger or the thumb. Now, if you look from the top, notice how a red glow can be seen. This is because only the red light frequencies are passing through the entire depth of the finger. Only red light has the ability to penetrate deep into body tissues.”
Figure 3 - Light Through Finger
The 6 Health Benefits of Red Light Therapy (Photobiomodulation)
Now, increasing ATP production inside our cells via photobiomodulation is super important. One needs to realise that this energy is not only used to keep us awake and feeling energetic.
But, the ATP is a universal fuel inside all living cells, which drive every single biological process we need to not only survive, but to thrive as well. Furthermore, it has now been discovered that ATP is also used as a signalling molecule that our cells use it to communicate with each other [4].
Cellular Growth
So, if new cells needs to be made, to grow or heal a bone for example, ATP is used to communicate with fibroblasts to initiate the bone remodelling process.
Figure 4 - Bone Remodelling Process
Cellular Clean-Up and Repair
Let’s say there are damaged, defective, or infected cells. These ATP signalling molecules communicate with macrophages to clean-up the mess, by engulfing and destroying the bad cells [4].
Figure 5 - Macrophages (Yellow) Engulfing Bad Cells
Immune System Regulation
How about when a virus enters our body? Again ATP signalling molecules can call upon killer-T cells and the like to destroy the pathogen.
Figure 6 - Killer-T Cells Destroying Pathogens
But hang on, what when our immune systems are over active and behaving irrationally, as in the case of autoimmune diseases? Well, communication to these cells to stop what they are doing and induce an anti-inflammatory response is also a possibility with better signalling [6].
Figure 7 - Immune systems can be over active and behave irrationally, as in the case of autoimmune diseases
The Bystander Effect
There are even studies that prove that activating ATP production through red and near-infrared light in one area of the body can have peripheral effects elsewhere.
For example, in one study the researchers used red light therapy to treat hyper pigmentation, called “malesma”, in women . However, they only shone the light on one side of the face. By the end of the study, there were massive improvements to the skin’s complexion on the treatment side, but the no-treatment side also showed improvement [3].
Figure 8 - Change in Skin Condition in the Face after Light Therapy
This is called “the bystander effect”, and it demonstrates that red and near-infrared light therapy has far-reaching systemic effects on the body through enhanced ATP molecular signalling [2].
Nitric Oxide Up-Regulation
Over and above ATP signalling, there are also some positive side effects of red light therapy. For instance, it stimulates the release of nitric oxide from the mitochondria and into peripheral tissue during ATP production [5][6]. This is awesome, because, as we know, nitric oxide is a powerful vasodilator, as well as a dilator of lymphatic flow. That means that more blood flow and lymph drainage can enhance oxygenation of cells, accelerate waste drainage, and many other good things [7].
Stimulation Of Reactive Oxygen Species
Additionally, the increased energy production of these red light stimulated cells results in a higher uptake of oxygen. The increased oxygen utilisation causes some oxidative stress to the cell via the production of reactive oxygen species (ROS) [5][7].
I know this sounds like a negative. I mean, why would we want our cells to be stressed? But, in fact, a small amount of oxidative stress is actually well tolerated by the cell because it stimulates the production of antioxidants to protect the cells, so it ends up being a therapeutic benefit [6].
It’s like when we stress out our bodies and muscles during exercise and they respond by becoming stronger and more adapted to the exercise-induced stress.
Summary of the Therapeutic Effects of Red Light Therapy
So, with all this in mind, it has been shown that cells that have been photoactivated by red and near infrared light will react in at least one of the following three ways, depending on the state they are in before exposure to the light [1]:
Cells will repair themselves – or self-destruct if they are damaged at the time after exposure.
The primary functions of the cell will be upregulated through their higher turnover of ATP.
If cell counts are low in the area of light exposure, new cells will migrate to that area or be stimulated to grow. This might also happened systemically through the bystander effect.
It almost sounds too good to be true, right?
Well, LED red light therapy is not some magic cure for everything. However, these spectrums of light are a natural component of our everyday lives, in the form of sunlight, which are proving to be highly beneficial for many cellular functions.
Light Therapy as a Pillar Of Health
Personally, I’m a firm believer that the most consistent factors that our lifestyle is made up of probably have the biggest impact on our health. These include: Nutrition, sleep, physical movement, breathing and light exposure. One could call these the pillars or fundamental elements of health.
Figure 9 - The 5 Health Pillars
For these reasons, photobiomodulation, in the form of red and near-infrared light therapy, is being used in many different kinds of therapies now.
The Use Cases For Red Light Therapy
Some examples are:
To promote hair growth. This was actually the reason for which the field of photobiomodulation came into being. In 1976, Dr Andre Mester conducted an experiment using a ruby laser, emitting red light, on induced tumour cells in mice [6]. Even though the experiment at the time was a failure, he did notice that the hair around the area that had been exposed to the ruby laser grew remarkably fast.
Figure 10 - Dr Andre Mester
From there the studies on photobiomodulation really took off. We now have proof of its effectiveness in skin care, diabetes, Alzheimer’s, sports and exercise performance, sleep, traumatic brain injury recovery, wound healing and much more. We also have much cheaper ways of gaining photobiomodulatory benefits from LED devices, as opposed to lasers.
We have reviewed one such LED device for home use, which can be found here:
JOOVV RED LIGHT THERAPY IN-DEPTH REVIEW | GO VS MINI SETUP
Additionally, if you want to grab yourself a Joovv Red Light Therapy device, the company has offered our audience a $50 discount with every purchase* using code EH on checkout on their website.
*Excluding the Joovv Go 2.0 device.
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