Red Light Therapy - 101

Humans are energetic beings, and light is a key fuel. While nutrition and exercise matter, light is essential for optimal cell function. Emerging research suggests that specific wavelengths can influence how our cells produce and use energy.

Advances in photobiology show that our bodies behave a bit like rechargeable batteries: light wavelengths help “power” us, while overall health governs how well we absorb and hold that charge. This principle underlies red-light therapy.

What is red light therapy?

Studies indicate that human tissue responds to selected bands of red and near-infrared (NIR) light. Devices such as light-therapy masks deliver these wavelengths to the skin, which may encourage mitochondria to produce adenosine triphosphate (ATP). Higher ATP output can support quicker cell repair and renewal.

Red (≈ 630–700 nm) and NIR (≈ 700–1 100 nm) photons penetrate to different depths. Red light is absorbed mostly in the upper skin layers and may promote collagen and elastin synthesis, potentially easing certain skin conditions. NIR light reaches deeper tissue and might improve local circulation and tissue oxygenation.

Recharging your body from within

Mitochondria generate the ATP that powers organs such as skin, heart, liver, and muscle. When red and NIR photons reach these organelles, they can stimulate electron-transport activity, raising ATP levels and supporting the cell cycle. This is why mitochondria are often called the “powerhouse” of the cell.

By exposing skin to therapeutic red/NIR light, users aim to give these powerhouses an extra spark, which may translate into faster recovery and healthier tissue over time.

 PubMed search: photobiomodulation |  PMC overview: low-level light therapy |  Harvard Health: skin therapies

1. LED light wavelengths from 630–800 nm (red) and 810–850 nm (near-infrared) pass through the skin and reach the cells when using a red light therapy device.
2. Inside the cell, light is absorbed by chromophores such as EZ water and the protein cytochrome c oxidase (CCO), which may boost mitochondrial activity.
3. This process can influence three key molecules: adenosine triphosphate (ATP), reactive oxygen species (ROS), and nitric oxide (NO).

Roughly 70 % of body weight is water, and 99 % of the body’s molecules are water-based, so water may play an important role in red light therapy.

Research by Prof. Gerald Pollack at the University of Washington suggests that water next to cells can form structured “EZ water,” which separates charge and may act like a microscopic battery.

What Does “Red Light Therapy” Mean?

“Red light therapy” usually describes natural-light treatments that deliver red and near-infrared wavelengths with LEDs or cold lasers, mimicking select bands of sunlight.

The term does not cover blue or white light, nor is it the same as full-spectrum or heat-based therapies such as infrared saunas.

Other names include RLT, photobiomodulation (PBM), phototherapy, LED therapy, infrared therapy, low-level laser therapy, or low-level light therapy (LLLT).

Red Light Therapy: A Multilevel Approach

By acting on cells and their environment, red light therapy may support healing at several levels throughout the body.

 PubMed search: photobiomodulation |  PMC overview: mechanisms of low-level light therapy

Molecular

 
• Adenosine triphosphate (ATP)
 
• Retrograde mitochondrial signaling
 
• Reactive oxygen species
 
• Water, opsins, chromophores, cytochrome c oxidase

Calcium

 
• Melatonin
 
• Gene transcription factors
 
• Heat-shock proteins
 
• Akt/mTOR/CyclinD1 pathway
 
• Brain-derived neurotrophic factor

Cellular

 
• Inflammation, cytoprotection, proliferation
 
• Protein synthesis
 
• Stem-cell production and migration
 
• Immune-cell viability
 
• Retrograde mitochondrial signaling
 
• Transforming growth factor
 
• Pro- and anti-inflammatory cytokines
 
• Vascular endothelial activity
 
• Mitochondrial membrane potential

Tissue

 
• Muscles: may boost endurance and tone
 
• Brain: may support cognition and immune balance
 
• Nerves: may aid repair and ease pain
 
• Bones, tendons, and wounds: may accelerate healing
 
• Hair: may increase growth
 
• Skin: may improve collagen network, lessen aging signs, and ease certain disorders
 
• Fat: micro-circulation gains may aid re-absorption
 
• Immunity and lymphatic flow: may improve

Systemic Effects: Positive Influences on Body Systems

Red-light therapy may influence several body systems at once:

Fascia

Fascia is the thin connective-tissue sheath that surrounds nearly every organ, muscle, nerve, blood vessel, and bone. Besides lending structural support, it is richly innervated, making it almost as sensitive as skin.

Although fascia looks like a single sheet, it is actually interwoven layers of collagen and elastin. Long overlooked, it is now recognized as a key pathway through which changes in one body region can affect another. Red light may enhance signaling within this fascial network.

Gut–Brain Axis

This information is educational and not a substitute for professional medical advice.

 PubMed search  Free full-text articles

The gut-brain axis links the brain’s emotional and cognitive centers with intestinal activity. Emerging work highlights how gut microbiota may modulate these interactions.

Red light therapy might support mood and neuropsychological balance by:

• Easing gut spasms and bowel inflammation.
• Encouraging neurotransmitter release, microglial activation, and local blood flow to help clear metabolic waste.
• Lowering blood pressure and improving circulation, which may lessen brain fog and anxious feelings.
• Modulating vagus-nerve signaling, a key channel between gut and brain that influences stress and social behavior.
• Shifting microbial composition.

Immune System

Red and near-infrared photons penetrate skin and reach cells, creating a mild metabolic challenge that can reinforce anti-inflammatory and antioxidant defenses, possibly making the body more resistant to infection.

Short, low-level red-light sessions appear well tolerated and may shape immune activity by:

• Supporting fibroblast proliferation, maturation, and migration.
• Prompting macrophages to adopt a phagocytic phenotype.
• Boosting fibroblast growth-factor output.
• Facilitating lymphocyte expansion and activation.
• Triggering controlled pro-inflammatory cytokine release and mast-cell degranulation.
• Ultimately damping excessive inflammation via mast-cell modulation.

Circulatory System

Studies suggest red light can raise micro-circulation and foster new capillary networks, improving oxygen delivery throughout the body.

Adequate oxygen and nutrient flow underpins cell growth, protein synthesis, tissue repair, inflammatory control, and angiogenesis, while also aiding removal of damaged cells.

Nervous System

PubMed search: gut-brain axisPMC overview: photobiomodulation

The nervous system—comprising the brain, spinal cord, neurons, and supporting cells—acts as the body’s command center. It governs movement, automatic responses, and vital functions such as digestion and breathing.

Red light therapy may influence the nervous system by:

 
• Releasing growth factors.
 
• Expanding the vascular network and increasing collagen.
 
• Supporting neural regeneration.
 
• Encouraging repair of nerve lesions and damaged nerves.
 
• Enhancing electrophysiological function.
 
• Promoting myelination of fibers.

For various forms of nerve damage, red light therapy offers a non-pharmaceutical option that may complement standard care.

Stem Cells

Preliminary work suggests red light therapy can boost stem cell activity, potentially improving outcomes after implantation. Early studies indicate it may stimulate mesenchymal stem cells in bone marrow, enhancing their migration to the brain and raising interest in exploring its role in neurodegenerative conditions such as Alzheimer’s, Parkinson’s disease, and dementia.

The Origins of Modern Red Light Therapy

Although red light therapy is now a popular natural and holistic tool, its roots trace back decades. NASA experimented with the technology during the 1980s and 1990s, and advances in LED lighting over the past 10–20 years have made clinical and at-home devices safer and more affordable.

In 2016, Led Mask introduced affordable light-therapy devices that the company describes as FDA- and MDASAP-approved.

 PubMed search: photobiomodulation and nerve repair  FDA device database

What is Holistic Medicine?

We mentioned red light therapy as a holistic option, but what does that mean? Holistic medicine treats the whole person—body, mind, and spirit—to support optimal function.

Principles of Holistic Medicine

Holistic medicine rests on three key ideas:

• Optimal health blends emotional, mental, spiritual, social, and physical well-being.
• Prevention comes first; treatment comes second.
• Illness arises from system-wide imbalance, not a single part.

Care therefore targets root causes, not just symptoms.

Six Core Benefits of Red Light Therapy

Red light therapy may offer many effects; six are most often reported.

Relieves Pain and Discomfort

Photobiomodulation (red/near-infrared light) has shown promise for carpal tunnel syndrome, mucositis, neck pain, menstrual cramps, temporomandibular joint pain, and neuropathic pain after amputation. It may also lessen hypersensitivity and improve sensorimotor function.

These changes appear linked to anti-inflammatory cell recruitment and other mechanisms:

• Down-regulates cyclo-oxygenase and prostaglandins
• Activates peripheral opioid receptors
• May boost endorphin and serotonin release
• Stimulates cellular metabolism
• Modulates nerve transmission

Repairs Skin

Red light may accelerate healing of burns, scars, bedsores, ulcers, surgical incisions, and diabetic neuropathy. NASA explored similar technology for wound care in space. Laboratory work suggests red and near-infrared light can support all four phases of wound healing.

PubMed search: photobiomodulation | NIH: wound healing overview

• Coagulation
• Inflammation
• Migration
• Remodeling
  

These processes are regulated by various factors linked through nitric-oxide (NO) signaling that is modulated by light energy.

A challenge the body faces during wound healing is limited oxygen delivery; red light may improve local oxygenation and support the natural repair sequence. By lowering inflammation and raising oxygen levels in the injured tissue, blood vessels can form more readily, which may accelerate repair and reduce pain and scarring.

Less pain can decrease the need for pharmaceutical analgesics while the wound heals.

Revives Immunity

The body gains energy at the cellular level, sustaining organ communication and disease resistance.

A robust immune system defends against harmful bacteria and viruses. Red-light exposure may lend extra support by releasing nitric oxide and melatonin, molecules involved in DNA repair and antimicrobial defense.

This response is termed hormesis. Red and near-infrared wavelengths penetrate the skin and enter cells, imposing mild metabolic stress that can trigger anti-inflammatory and antioxidant pathways.

With this support, the body may be better equipped to fight infections. Small studies suggest red-light therapy might:

• Improve melatonin production
• Raise NO levels
• Enhance antioxidant production
• Support thyroid function
• Prime T cells pre-operatively
• Increase neurotransmitter traffic
• Boost collagen and elastin production
• Encourage lymph-node activity
• Facilitate immune-cell transport
• Promote optimal cell and organelle function

Reduces Inflammation

Inflammation can be acute and local (short-term, from sprains, infections, or injuries) or chronic and systemic (long-term, driven by ongoing conditions).

 PubMed search: red light therapy inflammation

Acute inflammation is a healthy response, yet ongoing, widespread inflammation can undermine long-term health.

Standard care often relies on NSAIDs or steroids, which may slow tissue repair and carry cumulative risks. Red light therapy encourages the body’s own anti-inflammatory pathways, potentially lowering the need for prolonged medication.

Studies suggest red light can reduce inflammatory infiltrates, boost fibroblast proliferation (the cells that build collagen and matrix), promote angiogenesis, and trigger antioxidant defenses.

Small trials and pre-clinical work report improvements in conditions driven by acute or chronic inflammation:

• Arthritis
• Asthma
• Sinusitis
• Muscular sprains
• Fibromyalgia
• Neuro-inflammatory disorders such as Alzheimer’s disease
• Irritable bowel syndrome and colitis
• Rheumatic conditions

Supports Performance

Athletes increasingly use red light as a non-drug option that can be applied to many body areas.

By stimulating mitochondrial ATP production, the treatment may accelerate muscle repair and modestly improve subsequent performance.

Brief pre-exposure can precondition tissue, while post-session use is linked to faster recovery and less soreness.

Reported effects include:

 PubMed search: red light therapy inflammation  Mayo Clinic: chronic inflammation overview

• May ease DOMS (delayed-onset muscle soreness)
• Can support endurance and performance
• Might improve sleep quality
• May benefit sexual function and libido (including testosterone)
• Could aid weight-loss efforts
• May boost cognitive function
• Might lessen visible skin aging
• Can reduce the look of cellulite ‍

May lessen symptoms of depression and seasonal affective disorder

Seasonal affective disorder (SAD) is a type of depression that affects about 5 % of Americans during months with less natural sunlight. It is also called seasonal depression or the winter blues.

Bright white-light boxes are a common home remedy, but some researchers suggest that natural-spectrum options such as red-light therapy may also help offset light deficiency. In recent years, clinicians have occasionally added red-light sessions to standard psychotherapy or medication plans.

Who might use red light therapy?

While many people buy devices for home use, red-light systems are also found in professional settings:

Skincare professionals: Dermatologists and aestheticians sometimes use red-light therapy to encourage collagen, soften fine lines, and manage certain skin conditions.

Health practitioners: Dentists may apply it to reduce inflammation, physicians for mood support, and some oncologists to ease treatment side-effects.

Natural-health experts: Writers and podcasters such as Dr. Sarah Ballantyne, Ben Greenfield, and Dave Asprey have discussed potential benefits, as have Paleo and Keto voices including Robb Wolf, Mark Sisson, Luke Storey, and Dr. Anthony Gustin.

This information is educational and not a substitute for professional medical advice.

 Seasonal Affective Disorder (NIMH)  FDA Home  PubMed

Sports-Medicine Specialists: The National Academy of Sports Medicine (NASM) has incorporated red-light therapy into sports-injury protocols. Leading trainers and clinicians, including Dr. Troy Van Biezen and Dr. Ara Suppiah, use it to help athletes heal.

Elite Pro Athletes: Professional competitors around the world—among them NFL cornerback Patrick Peterson, former UFC champion Anthony Pettis, and Olympic gold-medal gymnast Sanne Wevers—report using red-light therapy to support performance and speed recovery.

Fitness & Training: Internationally recognized trainers such as Lacey Stone and Jorge Cruise employ red-light therapy to promote athletic output and muscle recovery.

Supportive Cancer Care: The Multinational Association of Supportive Care in Cancer (MASCC) recommends red-light therapy for oral mucositis, a common side effect of cancer treatment.

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Sources and References

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LED Lights Used in Plant Growth Experiments for Deep Space Missions. NASA.

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 PubMed search |  FDA device information

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Liu KH, Liu D, et al. Comparative effectiveness of low-level laser therapy for adult androgenic alopecia: a systematic review and meta-analysis of randomized controlled trials. Lasers in Medical Science. 2019 Aug.

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 PubMed database  ClinicalTrials.gov registry

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Preece D., Chow KW, Gomez-Godinez V., Gustafson K., et al. Red light may improve spermatozoa motility and did not induce oxidative DNA damage in this study. Scientific Reports. 2017 Apr.

American Psychiatric Association

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 PubMed search  FDA device database  Ongoing trials

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