The Science Of Red Light Therapy

Red light therapy, also known as Photobiomodulation (PBM) or low-level laser therapy (LLLT), is a therapeutic technique using red or near-infrared light (typically 650-1200 nm) that reaches tissues like muscles, bones, and nerves to stimulate various biological effects relevant for treating chronic conditions and cosmetic uses.

[Read for more details: What Is Red Light Therapy? The Basics Of Red Light Therapy And Photobiomodulation]

Key mechanisms of action are:

1) Stimulating cellular energy production: PBM’s effectiveness is rooted in its interaction with cellular components, particularly mitochondria which is responsible for cellular energy production. By facilitating increased electron transfer, it enhances ATP (adenosine triphosphate) production, and boosting cellular energy availability. This increased energy availability fuels various cellular processes, aiding in repair and regeneration.

2) Improving blood circulation: Another crucial mechanism is the release of nitric oxide (NO). Nitric oxide plays a vital role in regulating blood flow and vascular tone. When released, NO promotes vasodilation (the widening of blood vessels), enhancing blood circulation and delivering oxygen and nutrients to tissues. Improved circulation also aids in reducing inflammation and promoting healing in damaged or diseased areas.

3) Improving cellular healing: PBM also influences reactive oxygen species (ROS) levels, which are often associated with oxidative stress. At controlled levels, ROS can act as signaling molecules, triggering beneficial effects like cellular proliferation and repair. By modulating ROS, PBM contributes to a balanced oxidative environment conducive to healing.

These mechanisms lead to various biological effects and benefits.

[Read for more details: How Does Red Light Therapy Work?]

Biological Effects and Benefits

The biological effects of PBM are wide-ranging and can be harnessed for therapeutic benefits, including:

1) Anti-inflammatory Effects: PBM can reduce inflammation by influencing the cellular signaling pathways involved in the inflammatory response. The reduction in inflammation translates into pain relief and faster recovery times for injuries, making PBM an effective tool for conditions like arthritis and tendonitis.

2) Pain Relief: PBM has been shown to alleviate pain by modulating nerve activity and reducing inflammatory markers. This decreases nerve sensitivity, reducing the transmission of pain signals to the brain. Additionally, PBM influences the production of endorphins and enkephalins, natural pain-relieving compounds, further contributing to its analgesic properties.

3) Enhanced Tissue Repair and Wound Healing: PBM accelerates wound healing by helping fibroblast cells multiply to heal injuries and build new connective tissue. It also increases collagen production, improving the structural integrity of healed tissues and angiogenesis (the formation of new blood vessels), ensuring that the healing tissue receives an adequate supply of oxygen and nutrients.

4) Nerve Regeneration: PBM can reduce neuronal inflammation and promote the survival and growth of nerve cells. These effects make it a promising therapy for neurological conditions such as stroke, traumatic brain injury, and neurodegenerative diseases like Alzheimer’s and Parkinson’s disease.

5) Muscle Recovery and Performance Enhancement: PBM enhances muscle recovery by increasing mitochondrial function and reducing oxidative stress. Athletes benefit from PBM through quicker recovery after intense physical activity, reduced muscle soreness, and improved overall performance.

Because of these biological effects and versatile and non-invasive nature, PBM is used to treat a wide range of conditions.

"There have been a large number of both animal model and clinical studies that demonstrated highly beneficial LLLT effects on a variety of diseases, injuries, and has been widely used in both chronic and acute conditions. LLLT may enhance neovascularisation, promote angiogenesis and increase collagen synthesis to promote healing of acute and chronic wounds). [...] LLLT can also stimulate healing of deeper structures such as nerves, tendons, cartilage, bones and even internal organs. LLLT can reduce pain, inflammation and swelling caused by injuries, degenerative diseases or autoimmune diseases. [...] LLLT has been used to mitigate damage after strokes (in both animals and humans), after traumatic brain injury and after spinal cord injury." [Huang YY, Chen AC, Carroll JD, Hamblin MR.]

Clinical Applications

Some of the notable clinical applications include:

1) Chronic Pain Management: PBM is increasingly used for chronic painful conditions, including conditions like osteoarthritis, neuropathy, back pain, tendonitis & more.

2) Wound Healing and Tissue Repair: PBM has been effective in accelerating the healing of chronic wounds, such as diabetic ulcers, and acute injuries like surgical incisions.

3) Dentistry: It is also used in dentistry for conditions like periodontitis, where it promotes gum tissue regeneration and reduces inflammation.

4) Neurological Conditions: The application of PBM in neurological conditions is an emerging area of research. PBM shows promise in enhancing cognitive function and memory, as well as protecting neurons after strokes. For instance, studies indicate that PBM can reduce the volume of brain damage post-stroke by modulating inflammation and promoting cellular repair mechanisms.

5) Dermatological and Cosmetic Uses: PBM has gained popularity for cosmetic purposes, such as reducing wrinkles, improving skin texture, and enhancing hair growth. By stimulating fibroblast activity and collagen production, PBM helps rejuvenate skin and repair damage from aging and environmental factors.

"There have been a large number of both animal model and clinical studies that demonstrated highly beneficial LLLT effects on a variety of diseases, injuries, and has been widely used in both chronic and acute conditions. LLLT may enhance neovascularisation, promote angiogenesis and increase collagen synthesis to promote healing of acute and chronic wounds). [...] LLLT can also stimulate healing of deeper structures such as nerves, tendons, cartilage, bones and even internal organs. LLLT can reduce pain, inflammation and swelling caused by injuries, degenerative diseases or autoimmune diseases. [...] LLLT has been used to mitigate damage after strokes (in both animals and humans), after traumatic brain injury and after spinal cord injury." [Huang YY, Chen AC, Carroll JD, Hamblin MR.]