Red Light Therapy and Cancer (and more)

Researched and written by Keith Bishop, Clinical Nutritionist, Cancer Coach, Author, and Retired Pharmacist

Introduction: What is Red Light Therapy?

Red light therapy (RLT), also known as Photobiomodulation (PBM), is a non-invasive treatment that uses low-wavelength red light or near-infrared light to stimulate cellular function. It’s gaining traction for its potential to support skin health, reduce inflammation, and promote tissue repair.

RLT targets the mitochondria, the energy-producing centers of cells. When exposed to specific wavelengths (typically 600–850 nm), mitochondria absorb the light, stimulate mitochondrial cytochrome c oxidase, and produce more ATP (adenosine triphosphate)—the energy currency of the cell. This boost in cellular energy helps enhance healing, reduce oxidative stress, and decrease inflammation.[i]

Red Light Therapy and Other Health Issues

Beyond its cosmetic applications, RLT has been studied for its effects on several health issues, including:

• Skin rejuvenation: May reduce wrinkles, scars, and acne by stimulating collagen and fibroblast production.[ii]
• Wound healing: Shown to accelerate tissue repair and reduce inflammation.[iii]
• Muscle recovery: Used by athletes to reduce soreness and improve performance.[iv]
• Joint pain relief: May help with arthritis and other inflammatory conditions.[v]
• Rheumatoid Arthritis: Decreases the number of inflamed cells.[vi]
• Neurological support: Being explored for cognitive benefits in conditions like dementia[vii], Alzheimer’s[viii], and Parkinson’s[ix].
• Psychiatric Disorders: Major depressive disorder, general anxiety disorder, dementia, traumatic brain injury, schizophrenia, and sexual dysfunction.[x]
• Depression: Weekly application of 810 nm on the bilateral prefrontal area seems to be ideal for the maintenance of the antidepressive effects.[xi]
• Sleep: Whole body (PBM) Improves sleep quality, as determined by a subjective questionnaire and a commercial sleep tracker, including higher serum melatonin and lower nighttime heart rate in participants.[xii] 
• Eye Health: PBM can enhance treatment outcomes in several ocular diseases, including age-related macular degeneration, diabetic retinopathy, and dry eye disease. Patients undergoing PBM have reported improvements in visual acuity, reduced retinal inflammation, and better tear film stability.[xiii]
• Traumatic Brain Injury: Near-infrared light can penetrate the brain.  NIR light increases respiration in mitochondria (energy), causing activation of transcription factors, reducing inflammatory mediators and oxidative stress, and inhibiting apoptosis (cell death).[xiv]

How Deep Does Red Light Therapy Penetrate?

The depth of penetration of red light depends on its wavelength.[xv]

• Red light (600–700 nm) typically penetrates up to 5–10 mm (approximately 0.2 to 0.4 inches) into soft tissue. It's most effective for skin and superficial musculoskeletal applications. This level is often called low-level light therapy (LLLT).

• Near-infrared light (700–1100 nm) can reach 20–30 mm or more (approximately 0.8 to 1.2 inches), depending on tissue type, wavelength, and power density. This makes it suitable for deeper targets, such as joints, muscles, and even parts of the brain.

Red Light Therapy and Cancer

A group of researchers performed a systematic review of the current literature addressing the safety and efficacy of photobiomodulation therapy (PBMT) in cancer patients. They found a significant and growing literature indicates that PBMT is safe and effective, and may even offer a benefit in patient overall survival.[xvi]

In patients receiving surgery, chemotherapy and/or radiation therapy for head and neck cancer and breast cancer PBMT:

• Reduced oral mucositis (inflammation in the mouth and throat) and improved the long-term survival.[xvii]
• Reduced Epithelitis or acute radiation dermatitis[xviii] [xix]
• Decreased the incidence of acute dysphagia (swallowing problems), total parenteral nutrition (feeding liquids), and opioid pain medication use.[xx]
• Reduced Xerostomia (dry mouth).[xxi]
• With decongestive therapies provided a significant improvement in lymphedema (swelling)-related symptoms, arm mobility, emotional distress,[xxii] and reduced pain[xxiii] in patients with breast cancer and treatments.

Low Level Light Therapy (LLLT) in animals is not known to induce cancer to grow.[xxiv]

Emerging studies indicate that red light therapy may play a role in cancer treatment, particularly through photodynamic therapy (PDT). Research has explored its effects on skin cancers, esophageal cancer, lung cancer, and cutaneous T-cell lymphoma. A study on melanoma found that red light phototherapy inhibited tumor growth and enhanced immune response. Another investigation into hypoxic tumors—which are notoriously resistant to conventional treatments—demonstrated that red-light-activated compounds could induce cancer cell death even in low-oxygen environments.

Cancers Studied with Red Light Therapy

• Actinic Keratosis[xxv]
• Melanoma[xxvi]
• Breast cancer[xxvii] [xxviii]
• Head and neck cancer[xxix]

Red Light Therapy Impact on Chemotherapy-Induced Neuropathy

Researchers found that PBM proved to be a promising, low-cost resource for managing sensory symptoms of CIPN, with positive clinical repercussions on balance and gait speed.[xxx]

Neuropathic Pain Questionnaire (DN-4), the Chemotherapy-Induced Peripheral Neuropathy Assessment Tool (FANPIQ) and its interference items, and the Lower Extremity Functional Scale (LEFS) were used. Balance was assessed by measuring the amplitude, speed, and area of displacement with a force platform on rigid and deformable surfaces. Gait speed (GS) was assessed by the 10-m walk test.

Natural Compounds That May Enhance Red Light Therapy

PDT utilizes red light to activate photosensitizing agents, destroying cancer cells. Several natural compounds have been investigated for their potential to augment the effects of red light therapy, including curcumin, resveratrol, and epigallocatechin gallate (EGCG). These compounds are known for their antioxidant, anti-inflammatory, and anticancer properties, and emerging research suggests they may complement photodynamic therapy (PDT) when exposed to specific wavelengths of light.

• Curcumin: Found in turmeric, curcumin has demonstrated photosensitizing properties, meaning it can become more effective in generating reactive oxygen species (ROS) when exposed to red light. These ROS can help target and destroy cancer cells, making curcumin a potential adjunct in photodynamic therapy (PDT)- based cancer therapy.[xxxi] However, its poor bioavailability remains a challenge, leading researchers to explore nanoparticle formulations that enhance its absorption.[xxxii]
• I often recommend Onco-Adjunct Pathway 2 as a source of highly absorbed curcumin.
• Quercetin: A natural antihistamine, was found to enhance the effectiveness of PDT in treating Triple Negative Breast Cancer and Melanoma.[xxxiii]
• I often recommend Onco-Adjunct Pathway 2 as a source of highly absorbed curcumin.
• Berberine: Based on mechanisms of action, combining berberine with red light therapy MAY offer synergistic cancer benefits. At the time of publication, the combination of berberine and red-light treatment has not been evaluated.
• I often recommend Onco-Adjunct Pathway 3 as a source of highly absorbed berberine.
• Resveratrol: This polyphenol, commonly found in red grapes, has been studied for its ability to modulate oxidative stress, apoptosis, and inflammation in cancer therapy. Research suggests that resveratrol may enhance the cytotoxic effects of PDT when combined with light exposure, potentially increasing cancer cell destruction while protecting healthy cells from oxidative damage.[xxxiv]
• I often recommend Onco-Adjunct Pathway 4 for a source of highly absorbed resveratrol.
• EGCG (Epigallocatechin Gallate): A key component of green tea, EGCG has antioxidant and anti-cancer properties that may complement light-based cancer treatments. Studies indicate that EGCG can increase the susceptibility of cancer cells to oxidative stress, making them more vulnerable to therapies like red light therapy and PDT.[xxxv]
• I often recommend Onco-Adjunct Pathway 4 for a source of highly absorbed EGCG.

While these compounds show promise, their clinical applications are still under investigation, and further studies are needed to determine the optimal dosages, wavelengths, and treatment protocols. I recommend consulting with functional medicine practitioners who are familiar with supplements and red-light therapy, as well as your specific health challenges.

Methylene Blue and Red-Light Therapy: A Powerful Combination

Enhancing Mitochondrial Function

Methylene blue is a photosensitizer that has been studied for its ability to enhance mitochondrial function when combined with red light therapy. Research suggests that methylene blue can act as an electron donor, supporting the electron transport chain in mitochondria and improving cellular energy production. When exposed to red or near-infrared light, methylene blue stimulates cytochrome oxidase, a key enzyme in mitochondrial respiration, leading to increased ATP production and improved cellular metabolism.

Neuroprotective Benefits

Studies indicate that methylene blue, when combined with red light therapy, may offer neuroprotective benefits. Research has explored its potential in reducing oxidative stress, improving cognitive function, and supporting brain health. A study published in Frontiers in Cellular Neuroscience found that low-dose methylene blue and near-infrared light could protect neurons from degeneration, suggesting potential applications in neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Additionally, methylene blue has been shown to increase neuroplasticity, which may enhance memory and learning.

Applications in Functional Medicine

Beyond neurological benefits, methylene blue and red light therapy have gained attention in functional medicine for their anti-inflammatory, antimicrobial, and antioxidant properties. Some practitioners use this combination to support cellular repair, reduce inflammation, and improve metabolic function. Methylene blue has also been explored for its potential role in mental health treatments, with studies suggesting it may help reduce symptoms of depression and anxiety when paired with photobiomodulation.

While promising, further research is needed to determine optimal dosages, wavelengths, and treatment protocols for different conditions. To explore the latest studies, check out Frontiers in Cellular Neuroscience, Psychology Today, and Spectra Wellness.

Methylene Blue with Red Light Therapy and Cancer

Methylene blue, when combined with red light therapy, has shown promise in photodynamic therapy (PDT) for cancer treatment. As a photosensitizer, methylene blue absorbs red light and generates reactive oxygen species (ROS), which can induce cancer cell apoptosis and disrupt tumor metabolism. A systematic review of preclinical studies found that PDT using methylene blue led to tumor size reduction in multiple cancer types, including colorectal cancer, carcinoma, and melanoma. Additionally, research suggests that methylene blue may enhance the effects of chemotherapy and radiation, making cancer cells more susceptible to treatment. While these findings are promising, further clinical trials are needed to establish optimal dosages and protocols for integrating methylene blue with red light therapy in cancer care.

Potential Health Concerns of Red Light Therapy

Although red light therapy is generally safe, some risks should be considered:

• Overexposure: Prolonged use may lead to temporary skin redness or irritation.
• Eye Safety: Direct exposure to intense red light may harm the eyes, so protective eyewear is recommended during treatment.
• Skin Sensitivity: Individuals with light-sensitive conditions or those taking photosensitizing medications should consult a healthcare provider before starting RLT.
• Burns or Blisters: Using red light therapy for longer than recommended may cause burns or worsen certain skin conditions.

This blog is currently being written. Please check back for more information and Reference Sources.

Reference Sources

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[ii] Graeme Ewan Glass, Photobiomodulation: The Clinical Applications of Low-Level Light Therapy, Aesthetic Surgery Journal, Volume 41, Issue 6, June 2021, Pages 723–738, https://doi.org/10.1093/asj/sjab025

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