Red Light Therapy - The Optimum Guide
The Evidence-Based Health Benefits of Red Light and Near-Infrared Light Therapy
Are you ready to uncover some of the health benefits of red light and near-infrared light therapy? If so, you're in for a real treat! This blog will explore the evidence behind red and near-infrared light therapy, and show you how it can help with a variety of conditions. In addition to providing clinical evidence, this blog will also discuss the various benefits of red light and near-infrared light therapy in terms of skin health, inflammation, sleep quality, cancer prevention, and much more. Ready to see the benefits for yourself? Scroll down and get started!
How does red and near-infrared light therapy work?
Red and near-infrared light therapy is currently an emerging treatment for a variety of health conditions. There are numerous clinical studies and research about it. In a spectrum of wavelengths, only these two kinds of light are able to reach deep into our bodies. There are photoreceptors in our bodies to accept light energy and stimulate metabolic processes. All photobiological responses are determined by the absorption of energy by photoreceptor molecules during light irradiation, like the IR-induced photoreceptor (i.e., cytochrome c oxidase and intracellular water). Because of this, red and near-infrared light can activate the photobiomodulation process. This process is responsible for the production of photoprotective enzymes and other cellular responses.
There are some commonly acknowledged biological mechanisms that are affected by red and near-infrared light in the human body. For example, red light has been shown to increase the production of cytochrome c oxidase, which is critical in the last step of ATP synthesis in mitochondria, while red and near-infrared light therapy is thought to work by stimulating the production of endorphins—a type of neurotransmitter that helps reduce pain and inflammation. There are clinical studies that demonstrate the potent impact of red and near-infrared light on the acceleration of healing of some diseases or alleviating some syndromes.
Comparative studies of red and near-infrared light therapy
As is well known, red light (wavelength 630nm–640nm) can only travel through human tissue superficially, with the first 2 cm absorbing around 80% of light energy. Red light energy has a considerable impact on mitochondrial activation, which raises the amount of ATP produced and thus enhances fibroblast activity—for its facial application, cellular turnover, superficial circulation, and anti-inflammatory emission all rise as a result.
Compared to red light, near-infrared light (wavelength 800nm-850nm) can penetrate into tissue more deeply. Up to around 50% of light energy reaches the first 8 cm (NANS study). It is commonly known that infrared energy heats the tissue, and its benefits for treating pain are extensively established. For a cosmetic application, infrared light activates the Na/K+ pump, which enhances cell membrane permeability and helps maintain cellular PH balance while enhancing nutrient absorption and waste byproduct removal.
There are three separate layers of tissue that make up the skin; the epidermis (the outermost), the dermis, and the hypodermis (the innermost).
The epidermis ranges in thickness from 0.5 mm in areas of "thin skin" to 1.5 mm in areas of "thick skin" (the feet and hands, and particularly the heels); the dermis layer ranges from 1 to 4 mm, also depending on the locations; and the hypodermis includes skin muscles, bones, cartilage, tendons, lymph, blood, other organs, and interstitial fluid. Some tendons, knuckles, and cartilage that are just beneath the skin's surface can be reached easily by red wavelengths; however, some joints, notably the knees, as well as leg muscles, are rather large and need more research to determine how far the light therapy must travel for effective treatment, and the abdominal fat is necessary to be concerned about.
While both lights have similar functionality at a cellular level, there are differences in actual efficiency in science-proven studies. As a consequence, they render different applications of photomedicine. To determine optical effectiveness, researchers formulated the optical performance of tissue by optical coefficients, of which the most significant in relation to penetration ability is the absorption coefficient, which is affected by the absorption ability of cellular constituents under different wavelengths. That is why the penetration ability is mostly wavelength-dependent. The optics of the skin proved that different constituents are prone to absorbing different wavelengths. The main absorbing constituents are melanin, hemoglobin, and water. Though in the top layer of the skin, melanin and hemoglobin (in the blood) tend to absorb the majority of wavelengths below 600 nm, and above 905 nm is where water absorption starts to take over. Between 600 nm and 900 nm, where most light therapy devices apply, there is the lowest intersection of absorbing light energy, around the wavelength of 810 nm in this optical window, concerning the overall behavior of all absorption constituents, and it offers the best penetration. The result shows that the lower the absorption ability of tissue is, the deeper the wavelength can penetrate into human tissue.
There is more scientific evidence for treating different areas of the human body with different biological structures.
One study using the cadaver brain identified that via penetration profiles, the red wavelength of 660 nm reaches 21 mm and the 808 nm reaches 40 mm, which is helpful for brain-related treatment.
One study of the response of psoriasis to red laser light (630 nm) following systematic injection of hematoporphyrin derivatives shows optimistic results in the elimination of the syndrome. (https://onlinelibrary.wiley.com/doi/abs/10.1002/lsm.1900040110)
One study of low-level light therapy for androgenetic alopecia for both genders shows that red light (630nm, 650 nm, and 660 nm) is a safe and effective treatment for hair regrowth in comparison with placebo treatment. (https://onlinelibrary.wiley.com/doi/abs/10.1111/dsu.12200）
One study of red and near-infrared light on bone healing in vitro ATP production found that the red wavelength of 660 nm is essentially more effective than the near-infrared wavelength of 830 nm with fibroblasts or other light with osteoblasts. Worth mentioning is an insignificant increase in fracture healing in the group of 660 nm light. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5106470/)
One study of decaying skeletal muscle decline shows promising potential in the mitigation of muscle fatigue. In animal and clinical trials of low-level laser therapy using red, near-infrared, and mixed lights, it is demonstrated that red light at 660 nm combined with near-infrared light at 830 nm can give the most helpful assistance in muscle performance. (https://link.springer.com/article/10.1007/s10103-011-0957-3#Sec7)
One immunohistochemical study of a rodent model on the effect of low-level laser therapy on angiogenesis shows that the light at 660 nm presents elevated levels of collagen and increases the formation of blood vessels in the wound healing process. (https://www.scielo.br/j/bdj/a/k5ZzSv3hn6mCRZfd9rbQKMd/?lang=en)
One study in 2013 found that near-infrared light at 830 nm accelerated wound healing as well as had an effect on warding off secondary infection. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3799047/) Another study in 2015 showed that it was also beneficial in enhancing the results after plastic surgery. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4751092/)
One study in 2008 of bone healing reveals that laser therapy at 830 nm can stimulate bone regeneration in association with bone morphogenetic proteins. (https://pubmed.ncbi.nlm.nih.gov/18341420/)
Generally speaking, the penetration ability of light is chiefly dependent on wavelength, and according to different locations to be healed or conditions to be bolstered, the choice of wavelength is crucial. Red light therapy is sufficient for the majority of conditions, and near-infrared light therapy can reach deeper lesions or organs to provide a non-invasive solution, especially for psychiatric problems and brain-related conditions. However, it is generally believed that, in many cases, the mixed solution shows a better outcome than the solution of a single wavelength because the longer wavelength can amplify the effect of the shorter wavelength.
The better result comes from the combination of different depths, photon scattering, and direction change, which creates a net effect around the treatment area. While some studies show that energy transmission between red and near-infrared lights only varies by about 10% and the penetration depth is highly affected by experimental and clinical conditions, the mixed wavelengths are believed to trigger more synergistic processes around the treatment area.
When it comes to health-related matters, there is no one-size-fits-all answer. This is why it's important to conduct comparative studies of red and near-infrared light therapy before making a decision. Although both light wavelengths seem to have the same therapeutic effects, near-infrared light has the advantage of being more potent in healing deep organs or tissues. Additionally, when used in combination, the mixed red and near-infrared light is thought to be even more effective. So, if you're looking to get the most out of your health regimen, give red and near-infrared light therapy a try!
Effects of red and near-infrared light on various medical problems
Red light helps with skin rejuvenation
Skin aging takes its turn in the late 20s to early 30s and with wrinkles, dyspigmentation, telangiectasia, loss of elasticity, and other signs of skin aging come the fragmentation of collagen fibers, elastotic degeneration of elastic fibers and other molecular-level impotence. Common histologic and molecular-level features include the upregulation of matrix metalloproteinases (MMPs), especially MMP-1 and MMP-2, dilated and tortuous dermal vessels, and atrophy and disorientation of the epidermis. Both chronological and environmental influences are responsible for the aging process of the skin.
Currently, several modalities developed to reverse the dermal and epidermal signs of photo- and chronological aging requires intensive post-treatment care, due to the key concept of removing the epidermis and inducing a controlled form of skin wounding in order to promote collagen biosynthesis and dermal matrix remodeling. However, the discovery of RLT may provide a non-ablative approach to achieving this goal.
Skin problems such as acne and eczema appear to respond best to levels of red light waves near 650 nm. This wavelength stimulates the epidermis layer of the skin to produce more collagen and ATP.
Red light therapy promotes wound and bone healing
Because of the benefits, such as fastening surface microcirculation, reducing inflammation, regenerating fibroblasts and keratinocytes, etc., red and near-infrared light stimulates wound and bone healing. It also activates stem cells, which are crucial to the immune response as well as to healthy wound healing.
Red and NIR light therapy treats neurological conditions
Since the brain is one of the most mitochondria-rich organs in the human body, red and near-infrared light shows promising clinical results in brain performance. It also reduces oxidative stress (which is linked to neurodegenerative disorders like Alzheimer’s disease) and stimulates normal neurogenesis (birth of new brain cells), which aids in healing from traumatic brain injury.
NIR light therapy balances thyroid function
Thyroid function plays a root in overall health, by regulating metabolism through hormones. If a thyroid is underactive, a series of syndromes will happen, such as extreme fatigue, mental fog, weight gain, hair loss, and muscle weakness.
NIR light therapy promotes a healthy circadian rhythm.
As responsible for circadian rhythm, as well as highly photosensitive, the hypothalamus can be boosted through NIR therapy to activate melatonin production, which aids in getting quality sleep.
There are other potential benefits of red and NIR light therapy, including eye diseases, muscle performance, fat loss, and such. Though many studies are conducted under special experimental conditions in vitro and the amount of actual research in vivo is limited so far, many have shown a favorable effect in assistance with traditional treatment in various conditions. And its fundamental mechanism provides a safe and convenient new way to improve body health in a long run.
Other clinical experiments about red light and near-infrared light therapy.
Using red light therapy to rejuvenate the skin:
As noted in the review in the publication Seminars in Cutaneous Medicine and SurgeryTrusted Source, RLT may help rejuvenate the skin by:
- increasing collagen production in the skin, which gives the skin its elasticity
- increasing fibroblast production, which helps produce collagen and other tissue fibers
- increasing circulation between blood and tissue cells
- protecting cells from damage
- increasing mRNA in the cells, which helps stimulate the cell
- improving facial texture
- reducing fine lines
- reducing wrinkle severity
Using red light therapy to cure acne vulgaris:
The review in Seminars in Cutaneous Medicine and SurgeryTrusted Source also notes that forms of light therapy are potential alternatives for the treatment of acne vulgaris.
Sunlight can alter the way the sebaceous glands behave. The sebaceous glands produce sebum, which may clog the pores and cause acne. Sunlight may help calm overactive glands.
The behavior of the sebaceous gland can be changed by sunlight, and as a result, sunlight can calm the overactive glands, which secrete sebum to possibly clog the pores and cause acne vulgaris.
Using red light therapy to accelerate wound healing:
Research in the journal Anais Brasileiros de DermatologiaTrusted Source highlights the fact that light therapy may help wound healing in a few ways, such as by:
- reducing inflammation in the cells
- stimulating new blood vessels to form, which doctors call angiogenesis
- increasing helpful fibroblasts in the skin
- increasing collagen production in the skin
Using red light therapy to help hair growth:
A small study in the Journal of Cosmetic and Laser Therapy explored the effect of low-level light on people with alopecia. The outcomes verify that the effect was beneficial when people applied light at wavelengths of both 665 nm and 808 nm.
Using red light therapy to reduce pain:
A review in the European Journal of Physical and Rehabilitation Medicine compiled the results of many studies surrounding RLT and musculoskeletal disorders and indicated that RLT could effectively reduce pain in adults with different musculoskeletal disorders.
Using red light therapy to enhance bone recovery:
A review in the Journal of Photochemistry and PhotobiologyTrusted Source examines the potential for RLT in treating facial bone defects, and the results indicate that RLT may favor the speed-up of restoration after treatment for facial bone defects and the decrease of inflammation and pain.
Using red light therapy to reduce inflammation:
In many cases, RLT has a significant anti-inflammatory effect which has varied clinical applications. As research in the journal AIMS BiophysicsTrusted Source notes, many of the conditions that RLT treats have their roots in inflammation. Furthermore, studies have been taken to investigate its effect on chronic inflammatory diseases, such as:
- Alzheimer’s disease
- type 2 diabetes
- alopecia areata
- autoimmune thyroiditis, or inflammation of the thyroid
- tendinitis, or inflammation of the tendons
Frequently Asked Questions
Can red light therapy be used during pregnancy?
At this point, there is still much to learn about the effects of red light therapy on pregnant women and their children. However, studies have shown that red light therapy may be beneficial for reducing anxiety and stress levels in pregnant women. Additionally, it has been shown to improve fine motor skills, cognition, and language development in children exposed to red light therapy. But as with any type of treatment, more consultation is needed before making a decision. So until more conclusive evidence is found, it's ideal to ask for more help from a specialty of red light therapy during pregnancy unless you're specifically following a researched- and approved- treatment regimen.
What are common precautions to take when using red light therapy?
When it comes to red light therapy, always take the following precautions to avoid any risks or side effects: 1. Always wear protective eyewear to avoid damage to eyes from light of high intensity.
- Concerned about the time and dosage, overdoing it can cause fatigue, and provide no more beneficial effect on the treatment area.
- Always consult with a doctor before starting any type of light therapy treatment for medical purposes.
- Start with a small dosage and intensity of light therapy, before finding your own comfortable dosage.