Ultimate Guide to Red Light Therapy

Ultimate Guide to Red Light Therapy

Red light therapy (also known as photobiomodulation, red LED light therapy, or red to near-infrared LED therapy) is a type of treatment that uses light-emitting diodes to emit red and near-infrared light. It is also known as cold laser therapy, soft laser therapy, low-level light therapy, or low-power laser therapy because the light has a lower energy density than other kinds of light, such as UV light.

Red light therapy treatments are done using a device that emits red light and near-infrared light. These are defined by their wavelengths. Light of these specific frequencies penetrates beyond the skin to impact the entire body, improving both physical and mental well-being. 

The Origin of Red Light Therapy

Red light therapy treatments were developed by NASA in what can best be described as a happy accident. In the mid-90s, NASA scientists were experimenting with light-emitting diodes to grow potatoes on the space shuttle. In a surprising twist, it turned out that the red and blue LEDs also helped speed up healing of wounds. That is how NASA discovered the potential for medical uses of red light therapy, which could prove extremely beneficial during space travel, where astronauts' wounds heal slowly and their muscles and bones atrophy due to the lack of oxygen.

After discovering that high-intensity red and near-infrared light treatment sped up healing of wounds and the growth and proliferation of skin, bone, and muscle cell cultures in mice and rats, NASA team supplied LED devices to U.S. Navy crews for treatment of training injuries. These produced more than a 40 percent greater improvement in musculoskeletal injuries, as well as a 50 percent faster healing time for lacerations in comparison to control groups.

Since then, the development of low-level light therapy treatment led to much more sophisticated and effective devices. Modern red light therapy devices can be operated by anyone. They do not require handling by medical professional therapists, unlike laser therapy treatments. 

How Does Red Light Therapy Work?

With red light therapy, your skin is exposed to red light in the form of lights and lasers. Some cells, called mitochondria, or “energy generators” or energy generators of your cells, absorb this energy making it a lot better. 

It may help to strengthen your immune system and make it much more energy efficient. This promotes the regeneration of skin tissues and muscles. Red light therapy uses relatively little heat and is not painful. It does not provide as much illumination in tanning rooms and does not damage your face.

However, saying that red light therapy works by giving mitochondria enough energy means oversimplifying this entire process. This seemingly simple mechanism actually triggers a wide array of processes that affect almost every bodily function. Here are some of the most interesting effects of red light therapy:

Blood Flow Boost

As a result of mitochondrial functions, NO (Nitric Oxide) is released into the bloodstream. One of the most interesting effects of this process is that it causes the blood vessels to dilate. Dilated blood vessels mean that there is more room for the blood to circulate. Furthermore, this has from amazing secondary effects. If there’s a wound in the body, this means that the wound healing will be faster. 

This also means that the oxygen will reach the peripheral parts of the body to a greater extent. Another benefit is - all the nutrients necessary for optimal body function will reach their final destination quicker and more efficiently. Better blood flow is an essential systemic benefit of red light therapy.

Hormonal Balance

Red light therapy has been known to regulate the production of Melatonin. Usually called the “sleep hormone,” is much more than that. Given that Melatonin regulates our circadian rhythm, it also regulates when all the other hormones are secreted throughout the day. A disrupted sleep cycle also means the overproduction of stress hormones, adrenal fatigue, and many more negative effects on your body. 

Stem Cell Replication

In layman’s terms, your body sends stem cells to the rescue when dealing with a wound. Wound healing has three phases: the inflammatory, proliferative, and the remodeling phase. Stem cells have their role in each of them. That is why red light therapy has such excellent results regarding wound healing - it boosts stem cell replication so every healing phase can be more efficient.


Immune Response


Another thing red light therapy boosts is anti-inflammatory cytokine production. The role of these cytokines is to regulate the immunity response to inflammation. Therefore, it is not always about boosting immune response because that’s not necessarily the best scenario in all cases. In reality, it is all about tweaking the response to be optimal, effective, and efficient.

Why Red Light?

Red light therapy utilizes light from red light and near-infrared wavelengths, so that it can penetrate most of the tissue. The light can then easily be absorbed through a cell absorbing light. In particular, it has been proven that a combination of red and near-infrared wavelengths can yield the best results for one’s physical and mental health and overall well-being. 

Studies have shown that red and near-infrared wavelengths are absorbed by cytochrome C oxidase, a large integral membrane protein which is encoded in the mitochondrial genome and a key enzyme in cellular metabolism, which triggers a number of effects within the cell.

What Is the Difference Between Red and Near-Infrared Light?

There are several major differences between red light and near-infrared light. Firstly, red light is visible to the human eye while near-infrared is not. Secondly, red light wavelengths range between 630 and 700 nanometers, while near-infrared light are considerably longer, ranging from 800 to 2,500 nanometers. Perhaps most importantly, while red light is most effective for use on the surface of the skin, near-infrared light is effective both for use on the surface of the skin and for penetration of about 1.5 inches into the body.

Both red light and near-infrared light help increase cellular energy, reduce inflammation, increase collagen production and blood flow. However, red light is most useful in treating skin conditions, mental health problems, promoting healthy sleep, and improving mood. On the other hand, since near-infrared light penetrates deeper into the tissues, it promotes healing and cell rejuvenation and supports bone, muscle, and organ health.

The combination of red light and near-infrared light stimulates the production of collagen and elastin production associated with anti-aging benefits. That is why experts recommend it as an effective treatment for sun-damaged skin. Not only that, but red light and near-infrared light also provide a safe and successful treatment in reduction of fine lines, wrinkles, skin roughness, and intradermal collagen density increase, while also receiving high patient satisfaction rates.

Near-infrared light treatment has shown to improve recovery from stroke in certain patients, improved recovery from traumatic brain injury, as well as improvement in patients suffering from depression and anxiety.

There is also far-infrared light, which is closer to the microwave region of the electromagnetic spectrum, with wavelengths of 15 micrometers to 1 millimeter. The difference between far and near-infrared light is that the wavelengths of the former are the size of a pin head and the latter are microscopic, or the size of a cell. Far-infrared light has the potential for a wide-ranging application in the future, including manufacturing of bandages and dressings that could speed up healing of injuries, as well as performance-enhancing and cold weather apparel.

Is Red Light Therapy Effective?


Numerous studies prove the effectiveness of red light therapy treatments. Here are just a few dealing with specific health conditions.

Tendinopathy, which refers to various painful conditions occurring in and around tendons in response to overuse, affects 2 to 5% of people, and is particularly common with athletes and runners. A 2021 study has shown that there is evidence that low-level light therapy may be beneficial to those suffering from tendinopathy when used in addition to physical therapy.

Another study has confirmed that combination of red light and near-infrared LED light therapy represents an effective method of photo rejuvenation of facial skin. The treatments, which combined wavelengths of 633 nm and 830 nm, were evaluated at weeks 9 and 12 by profilometry performed on periorbital casts. By week 12, 52% of subjects showed improvement in photoaging scores, while 81% of subjects reported a significant improvement in periorbital wrinkles on completion of follow‐up.

Microbiome is a term used to describe the collection of all microbes, such as bacteria, fungi, viruses, and their genes, that live on our skin and inside our bodies. The composition and health of the gut microbiome affects many diseases related to metabolism, obesity, cardiovascular disorders, autoimmunity, and even brain disorders.

2019 research has demonstrated that the combination of red and near-infrared light delivered to the abdomen in both mice and human subjects can alter the gut microbiome in a potentially beneficial way for a number of different inflammatory and neurological diseases, such as cardiovascular and Parkinson's diseases.

More studies have researched the effect of soft laser therapy in promoting healing of skin wounds. One study has focused on decrease in inflammatory cells, increased fibroblast proliferation, angiogenesis stimulation, formation of granulation tissue and increased collagen synthesis. However, it is important to note that these results depended on an appropriate treatment, particularly regarding the wavelength and dose required to provide these benefits.

Another study specifically examined how low-level light therapy improved early wound healing by enhancing angiogenesis, marking this type of non-invasive treatment as a potentially cost-effective tool in complicated wounds.

What Are Red Light Therapy Benefits?

The benefits of red light therapy treatments on a molecular, cellular, and tissue level are practically endless. In particular, the applications of red light therapy on skin health and wound healing provide the most easily visible results, while also having an extremely high rate of patient satisfaction.

Low-level light therapy increases the proliferation of adenosine triphosphate (ATP), an organic compound that provides energy required to support numerous processes in living cells. This surge in ATP production speeds up cellular regeneration, energizes the entire body, and leads to rapid tissue regeneration.

Without the use of any damaging or invasive processes, red light therapy treatments significantly contribute to skin rejuvenation, improvements in skin complexion and skin elasticity. They help diminish skin roughness, fill out fine lines and wrinkles, as well as improve skin conditions such as acne or psoriasis. This is because red light therapy treatments stimulate collagen production in the skin and improve blood circulation.

Red light therapy regulates redox signaling, which supports metabolic processes and the function of the mitochondria, membrane-bound cell organelles whose main role is energy production. When you expose mitochondria to red light, proteins within mitochondrial membranes absorb the energy and increase the charge, leading to increased energy levels throughout the body.

Pain relief is another area where red light therapy is beneficial. Low-level light therapy treatments increase blood flow, causing the released endorphins to act faster and more efficiently. Red light also releases nitric oxide, a skin compound which lowers blood pressure, increases blood circulation, and improves blood flow to damaged or diseased tissues. Consequently, this leads to better management of pain mechanisms

Free radicals, also known as reactive oxygen species (ROS), are a by-product of mitochondrial metabolism. Because they are unstable oxygen-filled molecules that easily react with other molecules in a cell, their build up could damage DNA, RNA, proteins, and cause cell death in a process called apoptosis.

However, a basal level of ROS is essential for life because it supports basic cellular processes and viability. It is integral to redox signaling, cellular communication within a living organism required for normal physiological functions, like tissue repair, cellular proliferation and differentiation, immune response, circadian rhythms, and cell death regulation.

Low-power laser therapy helps keep the number of free radicals in the optimal range, thus protecting cardio-vascular health and the immune system. A clinical trial has identified that near-infrared light therapy treatments with wavelengths of 825 nm are particularly potent in generating ROS.

The above-mentioned cellular proliferation, a process of cell growth and division into daughter cells, is necessary for normal tissue development and maintenance over the lifespan. A red light of 660 nm was found to have a stimulatory effect on cell viability, proliferation and migration (including stem cells). This in turn promotes repair and wound healing and produces anti-inflammatory effects.

T-cells (also called T-lymphocyte and thymocyte) are a type of white blood cell that develop from stem cells in the bone marrow. They protect the body from infection by identifying and destroying other cells infected with viruses, bacteria, or other disease-causing microbes, and may help fight cancer. Red light therapy triggers bispecific T-cell engagers, which are emerging as one of the most promising immunotherapeutic strategies for cancer treatment in recent years.

Red light therapy also represents a potentially safe and effective treatment for melanoma. It has been found to prevent tumor growth and increase the expression of immune markers, proteins that determine our ability to resist harmful agents such as bacteria and other foreign substances, that are associated with favorable melanoma outcomes.

Red light can also be used as a part of photodynamic therapy, a treatment that uses special drugs, also known as photosensitizing agents, along with light to kill cancer cells. The photosensitizing agent is put into the bloodstream or on the skin, then low level light therapy activates the drug and causes it to form an oxygen molecule that targets and destroys diseased cells. This type of treatment is particularly beneficial for precancerous and cancerous cell growth and skin conditions such as psoriasis or warts.

Hormones are chemicals produced in the endocrine glands and released into the bloodstream, where they travel around and regulate many different processes in the body, including appetite and metabolism, sleep cycles, reproductive cycles and sexual function, body temperature and mood. When there is an excess or a lack of a hormone, it causes an imbalance that can considerably affect your well-being.

Undergoing red light therapy treatments can maintain optimal hormone levels by increasing melatonin and thyroid hormones, boosting testosterone, stabilizing circadian rhythm, energizing the mitochondria, and helping balance the gut flora. As previously mentioned, red light can also stimulate the production of ATP, which helps curb stress and fatigue and, in turn, regulates chemical imbalances.

It has also been proven that low-level light therapy raises levels of beta-endorphins, hormones produced in the brain, especially in the pituitary gland. They are involved in stress relief and pain management, and have a stronger effect than morphine on your body. By raising beta-endorphin levels, red light therapy can be used as a supplemental treatment for depression and anxiety.

According to the World Health Organization, an estimated 280 million people in the world experience depression. Seasonal Affective Disorder (SAD) is a type of depression caused by the shortening in day length and lower light intensity and affecting an estimated five percent of adult Americans. Red light therapy treatments can improve levels of serotonin, a brain chemical responsible for regulating anxiety, happiness, and mood. In this way, red light therapy can help to alleviate the symptoms of seasonal affective disorder, major depression, and perinatal depression.

Finally, red light therapy can also prove beneficial in efforts to lose weight, particularly when combined with regular exercise. Specifically, red light can help exercise efforts by reducing cellulite, improving sleep which is necessary for metabolism to burn fat, and increasing levels of T4, a type of thyroid hormone essential for weight regulation. 

Is Red Light Therapy Safe?

Red light therapy is perfectly safe. Since it does not use ablation or heating for its healing effects, there is no risk of burns or scars. Still, it is important to closely follow instructions, stick to the recommended dosages, mind the daily limit, and not stare directly into your red light therapy device.

It is advised that people in certain situations consult their doctor before using any form of red light therapy: those who are pregnant, are undergoing chemotherapy or taking medication that makes their skin photosensitive, have an active malignant disease, thrombo-embolism or bleeding, acute systemic infection, heart conditions, or highly photosensitive skin.

Even though there is no evidence that red light therapy would negatively affect people in these conditions, caution is still advised. 

What Are the Pros and Cons of Red Light Therapy?

In addition to numerous benefits mentioned above, perhaps the best thing about red light therapy is that it has absolutely no negative side effects. It is natural, non-invasive, and doesn’t cause tissue damage.

Near-infrared and red light therapy treatments use frequencies of light which don’t produce heat, so there is no risk of damage to the skin. They don’t emit UV rays, cause skin cancer, or increase chances of getting it.

On the other hand, red light therapy is not considered to be a main treatment for individual illnesses. As science and research progress, that can change in the future. For now, red light therapy is a fantastic supplement to other forms of therapy and wellness methods. It improves your life quality, nurtures your body and your energy levels, helping you reach your full potential.

You also have to be careful not to expose your body to too much red light therapy because your body will get used to it and no longer have a reaction.

Whether you purchase a red light therapy panel or take regular visits to the treatment center, red light therapy treatments can prove to be costly. What is worse, it is not highly likely to be prescribed by your doctor or covered by your health insurance.

Can You Use Red Light Therapy at Home?

Yes, you can absolutely use red light therapy at home provided you have access to a safe, effective, and clinically-tested device.

Portable red light therapy devices are convenient, easy to use, target the part of the body you want, and are thus more effective than therapy panels. You can take it everywhere you go, place it on an exposed part of the body you want to treat, strap it on and move around.

In the future, every household will be able to afford a portable, at-home, easy-to-use red light therapy device that will cost just a fraction of the price you would pay for yearly red light therapy treatments at a treatment center.

How Long Does It Take for Red Light Therapy to Work?

How long it takes for red light therapy to work is different and specific to each individual as every body is different. It may depend on many factors, including the device you are using, regularity of use, the type of condition you are treating, and your body’s individual responsiveness to red light therapy.

When it comes to using red light therapy for pain relief and healing of fresh injuries, first results may become apparent after only a week. For deep-seated conditions, it can take weeks. These should be taken as estimates, but within a few weeks of daily use, there should be visible signs of improvement.

If you are looking for natural, safe, non-invasive and chemical-free ways to transform your health, daily use of red light therapy at home can make all the difference. The list of benefits and research proving them is nearly endless, so whether you need help with skin care, wound healing, anxiety, depression, weight loss, sleep, hormone health, or the immune system, red light therapy is the reliable, science-supported way to do it.



  1. Rezaie, J., Zarrabi, M., Aslanpour, Z., Fouladdel, S., Azizi, E., & Aghasadeghi, M. R. (2017). Effect of photobiomodulation therapy on behavioral and biochemical parameters in experimental model of fibromyalgia in rats. Journal of photochemistry and photobiology. B, Biology, 169, 98-103. 

  2. Lee, S. Y., Park, K. H., Choi, J. W., & Kwon, J. K. (2014). Low-level light therapy for erectile dysfunction: a systematic review and meta-analysis. Journal of sexual medicine, 11(2), 264-277. 

  3. Liu, K. H., Liu, D., Chen, J. S., & Yu, B. Y. (2021). Using Red Light to Promote the Proliferation and Osteogenesis of Human Adipose-Derived Stem Cells: A Preliminary Study. Biomedicines, 9(8), 1065. 

  4. Gupta, A., Fischer, J., Mazhar, K., Ibrahim, S., Gollnick, H., & Hasan, T. (2021). Targeting Nitric Oxide with Photodynamic Therapy as a Novel Approach for the Treatment of Acne. The Journal of Clinical and Aesthetic Dermatology, 14(2), 22-29. 

  5. Brown, G. C. (1995). Nitric oxide and mitochondrial respiration. Biochimica et Biophysica Acta (BBA)-Bioenergetics, 1271(1), 214-220. 

  6. Zhu, T. C., Kim, M. M., & Dimofte, A. (2009). Light dosimetry calculations for interstitial photodynamic therapy of the prostate. Physics in Medicine & Biology, 54(18), 5543-5562. 

  7. Nam, J. H., Kim, W. H., & Kim, H. G. (2022). Efficacy of Green Light for Sleep Disorders in Korean Individuals. International Journal of Environmental Research and Public Health, 19(4), 2084. 

  8. World Health Organization. (2022). Depression. Fact Sheets

  9. Gupta, A., Avci, P., Dai, T., Huang, Y. Y., & Hamblin, M. R. (2013). Low-level laser therapy for fat layer reduction: a comprehensive review. Lasers in surgery and medicine, 45(6), 349-357. 

  10. Harvard Health Publishing. (2022). Light therapy: Not just for seasonal depression. Harvard Health Blog. Retrieved from 

  11. Poyton, R. O., Ball, K. A., & Castello, P. R. (2011). Mitochondrial generation of free radicals and hypoxic signaling. Trends in endocrinology and metabolism, 22(6), 259-265.

  12. Avci, P., Gupta, A., Sadasivam, M., Vecchio, D., Pam, Z., Pam, N., ... & Hamblin, M. R. (2013). Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring. Seminars in cutaneous medicine and surgery, 32(1), 41-52. 

  13. Kim, W. S., & Calderhead, R. G. (2017). Is light-emitting diode phototherapy (LED-LLLT) really effective? Laser therapy, 26(4), 305-315.