The Ultimate Guide to Red Light Therapy

The Ultimate Guide to Red Light Therapy

How to Use Red and Near-Infrared Light Therapy for Anti-Ageing, Fat Loss, Muscle Gain, Performance, and Brain Optimisation.

If there were a pill that was proven to have powerful anti-ageing effects on our skin, combat neurological disease, fight depression and anxiety, increase fat loss, speed recovery from exercise, increase strength and endurance, combat certain autoimmune conditions, fight hair loss, and speed healing from injury – all with little to no side effects – it would be a billion-dollar blockbuster pill. Hundreds of millions of people would be told to start taking it by their doctors every day. And doctors all over the world would call it a “miracle drug.”

Here’s the crazy part: That drug exists.

But it’s not a pill. It’s red and near-infrared light.

Red and near-infrared light therapy are one of the biggest breakthrough discoveries in health in the last 50 years. Scientists have quietly accumulated thousands of studies on the power of red and near-infrared light to enhance human health for the last several decades. And yet, most people have never even heard of it.

But before we get into the details, we need a little background on the science.

What is red and near-infrared light?

Red and near-infrared light are part of the electromagnetic spectrum, and more specifically, part of the spectrum of light emitted by the sun (and other sources of heat such as a fire). These wavelengths of light are “bioactive” in humans. That means that these types of light directly affect the function of our cells.

The Electromagnetic Spectrum

The electromagnetic spectrum is the range of frequencies (also called the spectrum) of electromagnetic radiation and their respective wavelengths which you can see below.

The whole spectrum is divided into separate bands, and the electromagnetic waves within each frequency band are called by different names; beginning at the low frequency (long wavelength, right-hand) end of the spectrum these are radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays at the high-frequency (short wavelength, left-hand) end. The electromagnetic waves in each of these bands have different characteristics, such as how they are produced, how they interact with matter and their practical applications.

Visible light – the electromagnetic waves that allow us to see the world around us – are in the wavelength of 380 nanometers (0.00038 millimetres) to 760 nanometers (0.00076 millimetres) and makes up all the colours of the rainbow. As you can see, this is a very narrow band of the spectrum.

If you pass white light (like sunlight) through a prism, it will separate out the different colours based on their wavelengths. This is how we get rainbows (the rain refracts the light), and you might remember this from school with the acronym ROYGBIV (or its mnemonic Richard Of York Gave Battle In Vain), which stands for red, orange, yellow, green, blue, indigo, violet.

Benefits of red and near-infrared light

Red light is in the frequency of 620-780nm, and near-infrared is in the frequency 780n-1100nm. These are the two we will focus on as these are the ones that give us the incredible benefits of Red Light Therapy. We will discuss below how Red Light Therapy can help the following conditions. We also link more benefits in the menu above.

Remember to visit our marketplace to view our Red Light Therapy products. And sign up to our mailing list for a 10% discount on all Red Light Products during December to celebrate our launch event.

How Red and Near-Infrared Light Affect Human Cells

In the 2018 textbook “Low-Level Light Therapy: Photobiomodulation,” Hamblin et al. give a detailed account of the history of how it came to be recognized that light influences human health.

In 1735, Fiennius described a case in which he cured a cancerous growth on the lip using a sunbath. In 1774, Faure reported that he successfully treated skin ulcers with sunlight, and in 1776, LePeyre and LeConte found that sunlight concentrated through a lens accelerated wound healing and destroyed tumours. There were also reports that sunlight had beneficial effects on internal maladies. In 1782, Harris used sunlight-exposed mollusc shells to improve a case of rickets (fragile bones due to vitamin D deficiency), In 1845, Bonnet first reported that sunlight could be used to treat tuberculous arthritis (a bacterial infection of the joints).

In the second half of the 19th century, the therapeutic application of sunlight, known as heliotherapy, gradually became popular. In 1855, Rikli from Switzerland opened a clinic in Veldes (now called Bled), Slovenia for the provision of heliotherapy. …

Theobald Adrian Palm (1848–1928) discovered the role of sunlight in the prevention of rickets. … Many years later, the role of sunlight exposure to the skin, in mediating the biosynthesis of vitamin D, eventually explained these observations.

Nils Ryberg Finsen (1860–1904)… suffered from an illness that would later be known as Niemann—Pick’s disease, which is characterized by progressive thickening of the connective tissue of the liver, heart, and spleen. His discovery that sun exposure improved his own symptoms encouraged him to treat his patients with light. He had particular success in 1893 when treating smallpox with red light and in 1895 when treating lupus vulgaris (also known as scrofula or cutaneous tuberculosis) with what he thought was ultraviolet light from an arc lamp (but was in fact probably blue light). …

Two pioneering Swiss physicians, Oskar Bernhard (1861–1939) at St. Moritz and Auguste Rollier (1874–1954) at Leysin, were responsible for extending the use of heliotherapy. Solar therapy as practised by these practitioners included increasing graduated exposures of parts of the body to sunlight, and the beneficial effects were considered to be enhanced by the fresh and cold mountain air in the Alps.

Bernhard obtained an impressive initial success treating a large non-healing abdominal wound (from a knife attack) that had resisted all other accepted healing approaches and which he decided to expose to the sun as a last desperate measure. Thereafter, he treated all nonhealing and infected wounds with sunlight. … In 1905, Bernhard had established his own small private clinic for sunlight therapy at St. Moritz that could accommodate some 33 patients and had south-facing balconies on two of the upper floors for convenient sun exposure.

Rollier … became disillusioned with the poor results obtained by surgery for the treatment of skeletal tuberculosis and went into a rural general practice … where he began to treat non-pulmonary tuberculosis with sunshine and fresh air. Over the next forty years, the technique Rollier devised for exposing the body to sunlight (Rollier’s Sunlight Therapy or Heliotherapy) came to be broadly accepted in Europe. His clinic, called “Les Frênes,” was the first large, purpose-built sunlight-therapy facility to be constructed in the world.”

Thus, the general concept that sunlight was a powerful form of medicine (and even necessary for human health and the prevention of diseases like rickets) became general knowledge.

So where do red and near-infrared light come into all this?

There have now been literally thousands of studies conducted upon both animals and humans. Overall, red light has been repeatedly shown to have positive effects on cell function in animal and human studies and aid in improving a wide range of conditions, improving health in numerous ways. Red and near-infrared (NIR) light therapy devices have been FDA-approved for several purposes so far, including anti-ageing, hair-loss reversal, acne treatment, pain relief, slow to heal wounds, fat loss, among other purposes. (This is worth noting as it proves the abundance of research showing benefits—the therapy has to be proven safe and effective in numerous trials to gain FDA approval.)

The Five “Bioactive” Types of Light: Why Humans Need Sunlight to Be Healthy

These are the five types of bioactive light in humans:

  1. Bluelight—sets the circadian rhythm in our brain, which in turn regulates numerous different neurotransmitters and hormones (which is why it’s recommended to switch off the computer, the TV and put down the phone or tablet long before bed – see below)
  2. UV light—allows us to synthesize vitamin D from the sun
  3. Far-infrared—acts to heat up our cells (this is the part of the sun’s spectrum that you feel as heat) which stimulates changes in cell function, as well as circulation changes
  4. Red light—acts on the mitochondria in our cells to stimulate increased cellular energy (ATP) production (among other mechanisms discussed in this book)
  5. Near-infrared(NIR)—acts on the same pathways as redlight—particularly in the mitochondria in our cells to stimulate increased cellular energy (ATP) production (among other mechanisms)

Our ancestors didn’t have to worry about all this living outdoors in the sun, they were able to get exactly what the body needed at the right dose.

But in the last few generations, modern humans have made the switch to living indoor lives with electricity, man-made artificial lighting systems and limited sun exposure. Therefore, we have developed light deficiencies and toxicities that are having a massive impact on our health and well-being.

The point is that modern humans are deficient in the benefits of all of these five wavelengths of light, and there are health consequences when we don’t get enough.

What kind of health consequences?

The most common light-related health problems that most people are already familiar with are vitamin D deficiency (from too little UV light) and circadian rhythm disruption (from too little blue light in the morning, and too much artificial light at night). Just these two light-related health issues alone are responsible for a massive burden of disease in the modern world. These two issues caused by inadequate and improper light exposure are linked with dozens of types of cancer, as well as heart disease, obesity, diabetes, neurodegenerative disease, and multiple other conditions.

Sunlight deficiency has been linked with numerous diseases, such as:

  • Neurodegenerative diseases like Alzheimer’s, dementia, Multiple Sclerosis, and Parkinson’s
  • Dozens of types of cancer
  • Obesity
  • Diabetes
  • Metabolic syndrome
  • Heart disease

As another example of mal-illumination, artificial light exposure at night (from electronic devices like phones, TVs, computers, indoor lighting, etc.) have been linked with numerous diseases, like:

  • Numerous types of cancer
  • Depression
  • Fat gain, obesity, diabetes and metabolic syndrome
  • Insomnia and poor sleep
  • Mood disorders

But what if we told you that there is another kind of light deficiency that most people are totally unaware of, and that is likely even more problematic?

Red and near-infrared (NIR) light deficiency.

We used to be exposed to far more light and of the right wavelengths because our ancestors spent hours each day working under the sun and spent evenings around the fire, both of which emit ample red and near-infrared light. Thus, humans never had to think about this subject for hundreds of thousands of years—our outdoor lives in the sun took care of our daily red and near-infrared light needs.

But now, most peoples’ light exposure habits are the equivalent of eating an all-McDonald’s diet all day, every day. Complete mal-illumination.

We used to be exposed to far more light and of the right wavelengths because our ancestors spent hours each day working under the sun and spent evenings around the fire, both of which emit ample red and near-infrared light.

While most other wavelengths of light (such as UV, blue, green, and yellow light, etc.) are mostly unable to penetrate into the body and stay in the layers of the skin, near-infrared light and red light are able to reach deep into the human body (several centimetres – close to 2 inches – in some cases) and are able to directly penetrate into the cells, tissues, blood, nerves, rods and cones of the eyes, the brain, and into the bones. You can see that in this diagram:

Once in those deeper tissues, red light and near-infrared (NIR) light have incredible healing effects on the cells where they can increase energy production, modulate inflammation, relieve pain, help cells regenerate faster and much more.

Remember to visit our marketplace to view our Red Light Therapy products. And sign up to our mailing list for a 10% discount on all Red Light Products during December to celebrate our launch event.

How Does Red and Near-Infrared (NIR) Light Therapy Work?

Without going into full scientific depth – you can read Hamblin’s book (et al) for that, Red/NIR light has been shown in research to affect all of the following compounds and pathways:

Molecular Mechanisms

  • Cytochrome c oxidase: This is a photoreceptor located on mitochondria in our cells that “accepts” light photons and then triggers events in the mitochondria. (More detail on this below.)
  • Retrograde mitochondrial signalling: This is a key factor where mitochondria in the cells communicate with the nucleus of the cell about what is going on, thus affecting what genes get expressed in the DNA-containing nucleus of our cells.
  • Light-sensitive ion channels: There are channels in our cells which control the flow of various ions (e.g. calcium, potassium, sodium, etc.). Some of these are affected by light and then are involved with triggering further events in the cell or between cells.
  • Adenosine triphosphate (ATP): This is cellular energy produced by mitochondria. One of the more notable findings from many studies is that exposure to red/NIR light increases levels of ATP production.
  • Cyclic AMP: This is involved with opposing inflammatory pathways, among other functions in the cell.
  • Reactive oxygen species (ROS): These are also commonly called “free radicals.” While commonly associated with bad things (e.g. cell damage, oxidation, etc.), they also play vital roles in our bodies as signalling molecules. For example, ROS are produced from physical exercise and signal many of the positive adaptations that our body makes to exercise.
  • Calcium: Red/NIR light can affect calcium levels in the cell, which in turn act as a signal for numerous cellular processes.
  • Nitric oxide (NO): It is known that NO levels rise after red/NIR light exposure. NO is well known by most people for its role in blood vessel dilation, but it also acts in many other signalling pathways. (More on this below.)
  • Nuclear factor kappa B: This is a signalling compound that regulates many genes involved in inflammation and cell survival to stressors.
  • RANKL: A protein involved in bone regeneration/remodelling.
  • Hypoxia-inducible factor: A protein involved in cellular adaptation to low oxygen levels.
  • Akt/GSK3b/b-catenin pathway: This pathway relates to cell survival and apoptosis (programmed cell death).
  • Akt/mTOR/CyclinD1 pathway: Involved in cell growth signalling.
  • ERK/FOXM1: Involved in regulating cell division.
  • PPARy: Involved in the inflammatory response.
  • RUNX2: Involved in bone cell differentiation.
  • Transforming growth factor: Stimulator of collagen production (e.g. in the skin).
  • Pro- and anti-inflammatory cytokines: Many pro- and anti-inflammatory cytokines and mediators have been shown to have their levels altered by red and near-infrared light exposure.
  • Vascular endothelial growth factor: Involved in angiogenesis—the formation of new blood vessels.
  • Hepatocyte growth factor: Involved in liver cell health.
  • Basic fibroblast growth factor and keratinocyte growth factor: Involved in the wound healing process.
  • Heat-shock proteins: Involved in inflammation, wound healing, and cellular survival against many types of stressors (e.g. exercise, sauna/heat stress, etc.).
  • Melatonin: Interestingly, red/NIR light therapy has been shown to increase “extra-pineal” production of melatonin outside of the pineal gland. Melatonin is much more than just a sleep-inducing hormone as most people know it—melatonin has critical roles in protecting the mitochondria from damage and supporting glutathione levels, which is one of our body’s most powerful and important antioxidants and detoxifying compounds. Some researchers have suggested that this increased melatonin may be a significant factor in the effects of red/NIR light.
  • Brain-derived neurotrophic factor: Involved in neuron/brain cell growth and regeneration.

Cellular Mechanisms

  • Inflammation: One of the most important cellular mechanisms that red/NIR light have is their effect on inflammation pathways. It appears to do this through inhibition of inflammatory prostaglandin PGE2 production and expression of COX-1 and COX-2, as well as inhibition of the NF-kB pathway. The net effect: Reduced inflammation.
  • Cytoprotection: Various studies have shown that red/NIR light can help protect cells from dying after being exposed to various toxins (e.g. methanol, cyanide, etc.). It appears to have a cell-protective effect in some instances.
  • Proliferation: Some types of cells (e.g. skin cells, bone cells, cells that line blood vessels, etc.) have been shown to grow and replicate faster with exposure to red/NIR light.
  • Migration: Some types of cells (e.g. tenocytes in tendons or melanocytes in the skin) need to actually move to get to the location they’re needed. Some research has shown that red/NIR light can stimulate this.
  • Protein Synthesis: Red/NIR light can also stimulate cells (e.g. skin cells, bone cells, etc.) to produce more proteins (e.g. collagen).
  • Stem Cells: Stem cells are apparently even more sensitive to red/NIR light. Red/NIR light has been shown to positively affect growth, movement, and viability of stem cells. This may be relevant to both stem cells already present in our body, as well as in the context of stem cell therapy.

Tissue Mechanisms

  • Muscles: Numerous studies have shown that red/NIR light affect muscle performance, recovery from exercise, and adaptations (i.e. enhanced strength, endurance, muscle growth, fat loss) to exercise. (These studies are discussed in this book in later sections.)
  • Brain: Red/NIR light has been shown to benefit brain function as well. Studies have shown improvements in cognitive performance and memory, improved functioning after traumatic brain injury, improved mood, as well as improvements in certain neurological diseases (e.g. Alzheimer’s disease). The improvements in mitochondrial function, reduction in inflammation, and increased Brain-Derived Neurotropic Factor (BDNF) likely all play a role in enhancing neuron health.
  • Nerve (Pain): Some studies have shown that red/NIR light can dull pain due to blocking conduction at nerve fibres. Anti-inflammatory actions, as well as blocking of substance P, likely play a role in this effect.
  • Healing (Bones, Tendons, and Wounds): Numerous studies have shown that red/NIR light can stimulate and accelerate healing of numerous types of injuries—from tendon/muscle/ligament tears to bone fractures, and skin wounds. This is likely by affecting local growth factors involved in cellular repair, as well as effects on the inflammatory processes.
  • Hair: Red/NIR light is also used in the context of hair re-growth, and numerous studies have shown it to be effective for this purpose. This is likely due to local blood vessel dilation and anti-inflammatory effects.
  • Skin: Numerous beneficial effects on skin wrinkling and laxity, cellulite, collagen production and other aspects of skin health have been found. Anti-ageing of the skin is one of the most common uses for red/NIR light.
  • Fat: The exact mechanisms of how this happens are still debated among researchers, but numerous studies have shown that red/NIR light can stimulate the release of fatty contents from fat cells, and ultimately, lead to body fat loss.

Two Key Mechanisms of Red/NIR Light Therapy

Having gone through this more complete list of factors and mechanisms, now I want to simplify and condense the science. I generally think of red/NIR light as having two central mechanisms in how it benefits cellular function and overall health:

  1. Stimulating ATP production in the mitochondria through interacting with a photoreceptor called cytochrome c oxidase.
  2. Creating a temporary, low-dose metabolic stress (known as hormesis, which is also a primary mechanism of why exercise works) that ultimately builds up the anti-inflammatory, anti-oxidant and cell defence systems of the cell.

The Real Benefits of Red/NIR Therapy

In essence, red and near-infrared light “fires up” this engine of the cell, driving ATP production by the mitochondria. And since everything cells do depend on energy supplied by the mitochondria, red light and near-infrared light therapy have been linked with a wide range of amazing benefits:

  • Anti-ageing effects in the skin (enhancing collagen synthesis, production, and elastin production for youthful skin and dramatically reducing cellulite)
  • Lowering inflammation
  • Enhancing fat loss
  • Enhancing physical performance and muscle recovery afterwards
  • Boosting testosterone
  • Speeding wound healing
  • Spurring neurogenesis in the human brain, strengthening synapses, spurring brain cell growth
  • Helping prevent cognitive decline
  • Reducing waist circumference and liberating fat from cells so it can be burned again
  • Enhancing physical performance and muscle recovery afterwards
  • Enhancing fertility
  • Combatting gingivitis and promoting healthy gums
  • Enhancing stem cell implantation and proliferation
  • Enhancing gland health from the thyroid to the lymphatic system
  • Clearing skin for sufferers of acne, rosacea, eczema, psoriasis
  • Improving eye health
  • Fighting chronic fatigue and fibromyalgia
  • Potentially helping the body to fight cancer (in tandem with chemotherapy)
  • Removing wrinkles, lines, and veins on the surface of the skin
  • Increasing energy
  • Improving the appearance of scars
  • Killing pain
  • Protecting cells against damage from stress

Remember to visit our marketplace to view our Red Light Therapy products. And sign up to our mailing list for a 10% discount on all Red Light Products during December to celebrate our launch event.


Small Print

The content of this website is for general information and education only and are not intended to be a substitute for professional medical advice, diagnosis or treatment. None of the information on this site should ever be interpreted as a claim of treatment or cure of any medical condition. Readers should not rely exclusively on information provided on this site for their own health needs. All specific medical questions should be presented to your own health care provider. Diagnosis and treatment of any medical conditions are strictly for you to discuss with your doctor.

The intention of this site is to provide information about scientific research as it relates to red and near-infrared light therapy. We also have attempted to provide guidelines for using red and near-infrared light therapy devices safely. None of the information on this site and none of the guidelines for safe usage of devices should ever be interpreted as claims of diagnosis, treatment, or cure of any medical condition.

Lightnet does not assume any risk for your use of this site. In consideration for your use of this site, you agree that in no event will Lightnet be liable to you in any manner whatsoever for any decision made or action or non-action taken by you in reliance upon the information provided through this site.

All the information in this site is published in good faith and for general information purpose only. We do not make any warranties about the completeness, reliability and accuracy of this information. Nor is anything in this site to be considered a guarantee of benefit or a claim of improvement for any medical condition. Any action you take upon the information on our website is strictly at your own risk. And we will not be liable for any losses and damages in connection with the use of the information in this site.