What Is Red Light Therapy?

Red light therapy is a procedure using light-emitting diodes (LEDs) to treat medical and cosmetic conditions. It sends low-intensity red and near-infrared light deep into the body’s cells to stimulate healing. It is noninvasive, painless, and does not use heat.

Hungarian physician and professor Endre Mester first used red light therapy in 1967 while studying how cancer cells react to radiation exposure. Today, this treatment is used in medical, dental, spa, and home settings to help repair tissue and relieve pain and inflammation.

woman red light therapy clinic

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Red light therapy goes by several names, including:

  • Photobiomodulation (PBM) or photobiomodulation therapy
  • Low-level laser light therapy (LLLT)
  • Low-power laser therapy (LPLT)
  • Cold laser therapy
  • Biostimulation
  • Photonic stimulation
  • Soft laser therapy

Red light therapy is part of photodynamic therapy as well. In this case, red light activates an agent to help the skin absorb more light.

This article will discuss the mechanisms behind red light therapy and how well it works for a variety of conditions.

How Does Red Light Therapy Work?

Red light therapy uses low-power red light to activate mitochondria, which are the cell’s energy generators. Most of the energy produced by the mitochondria is housed in a molecule called adenosine triphosphate (ATP), which helps your body store and use energy.

Aging, illness, or lifestyle factors can make the mitochondria produce less ATP. Red light therapy triggers a reaction that helps reverse this decline.

Why Red Light?

Red light therapy uses light in the red or near-infrared region because this wavelength range best penetrates through tissue. It is more easily absorbed by the parts of cells that capture light energy.

More Research Is Needed

Medical evidence is growing in support of red light therapy. However, many studies include small samples, animal subjects or in vitro means (using a test tube or petri dish in a lab), and inconsistent standards. More trials are underway to confirm this treatment's effectiveness.

How Is Red Light Therapy Used?

Red light has been used for a variety of reasons, including in the treatment of skin, dental, and inflammatory conditions.

Skin Conditions and General Skin Health

Red light therapy is a popular option for treating redness, scars, acne, and wrinkles. This may be due to the light's effect on collagen production and blood circulation in skin tissue. Red light therapy may help in the following ways:

  • Antiaging: Red light therapy is used to enhance the appearance of skin that has been damaged or aged by sunlight. It may stimulate the rapid production of cells that secrete collagen proteins. This helps lift and tighten lax skin, reducing wrinkles. 
  • Acne: Cold laser therapy could be an effective treatment for acne vulgaris, but evidence is scarce. The light might decrease inflammation, irritation, and sebum production in the skin. 
  • Hair growth: Low-level laser light therapy may help treat pattern hair loss in women and men, but more research is needed.
  • Wound healing: Red light therapy has the potential to help heal chronic wounds. The technique might also encourage new skin growth and help new blood vessel networks form.

Dental Pain

Dental professionals turn to red light therapy to help relieve a variety of oral problems. The treatment can reduce pain, inflammation, and ulcers. It also helps keep unhealthy oral microbes in check. The following treatments make use of red light therapy:

  • Temporomandibular dysfunction (TMD): TMD causes discomfort and clicking in the jaw, as well as limited jaw movement. Red light therapy can relieve pain, increase range of motion, and improve muscle activity in people with this condition.
  • Periodontitis: Red light therapy can help treat periodontitis, a chronic buildup of dental plaque bacteria. Along with photodynamic therapy, this procedure may help reduce the bacteria associated with this type of buildup. 
  • Burning mouth syndrome: Low light laser therapy has helped decrease painful symptoms in postmenopausal women with burning sensations in the mouth. 
  • Stomatitis: Minor recurrent aphthous stomatitis (MiRAS) is marked by painful lesions on the lips, soft palate, and the lining of the cheeks. In a 2020 study of children aged 5–12 years old, red light therapy reduced pain and the size of MiRAS ulcers within two weeks.

Inflammation

Red or near infrared light spurs cells to speed up the production of antioxidants and lower inflammatory markers. Soft laser therapy can increase circulation to help relieve inflammatory conditions without drugs or surgery, including:

  • Osteoarthritis: Several studies have found that red light therapy can reduce pain and disability in individuals with knee osteoarthritis. The benefits even extended up to 12 weeks after the end of treatment.
  • Tendinitis: Pre-exercise red light therapy might improve sports performance and speed recovery from muscle strain. This may be due to the treatment’s potential to combat oxidative stress caused by exercise.
  • Psoriasis: Cold laser therapy is a common treatment for mild to moderate psoriasis, an autoimmune inflammatory skin condition. However, each type of this disease needs different light sources to be effective and avoid skin burning or other adverse effects.
  • Carpal tunnel syndrome: In one study, low-level laser therapy helped reduce carpal tunnel syndrome pain in the hands significantly. It also enhanced electrical activity in the median nerve.

Other Conditions

Red light therapy helps support the body's natural healing process. Cold sores, dementia, and mood disorders also respond to this treatment, as follows:

  • Herpes cold sores prevention: Red light therapy may successfully prevent and treat recurrent cold sores, a common infection caused by the herpes simplex virus. However, more studies are needed to confirm this.
  • Alzheimer’s disease: Formaldehyde concentrations in the brain are associated with oxidative stress and memory loss. Research suggests that red light therapy can break down formaldehyde to improve cognitive function in adults with mild to moderate Alzheimer’s disease, a progressive brain disorder.
  • Anxiety: In a 2019 study, brain stimulation with red light helped improve anxiety symptoms in individuals with generalized anxiety disorder. The participants were also able to sleep better after treatment. 

Unproven Claims

People commonly use red light therapy to help the following conditions. However, science has yet to confirm the treatment’s usefulness for:

  • Seasonal affective disorder (SAD): A 2019 review determined that not enough evidence supports red light therapy as a treatment for seasonal affective disorder, a type of depression related to seasonal change.
  • Weight loss: No reliable studies support any weight loss benefits of red light therapy. However, limited research shows that the treatment may help reduce waist circumference.
  • Low back pain: In several controlled trials, red light therapy did not affect pain and disability in individuals with chronic, nonspecific lower back pain. Seemingly positive outcomes were based on low-quality evidence.
  • To activate cancer treatments: According to a 2021 review, low-level laser light therapy may help aid cancer treatments. However, the long-term safety of its use on or near tumors hasn’t been proven.

Pros and Cons of Red Light Therapy

When considering cold laser therapy, it's important to weigh its potential advantages and risks. You can find practitioners or devices in many convenient settings, but this treatment may not work for everyone.

Benefits

Red light therapy is nontoxic, noninvasive, and considered safe for all skin types. It does not require the use of harsh topical substances or heat which can irritate or burn the skin.

Also, the treatment does not use ultraviolet (UV) light, which is reported to cause skin cancer.

Red light therapy is easy to access at medical or dental offices, spas, tanning salons, or beauty clinics. At-home devices are also widely available.

Side Effects and Risks

There are no set guidelines for how long or strongly red light therapy should be applied, so there is a slight chance of adverse effects. Also, the long-term safety of this procedure is yet to be determined. If you use red light therapy devices incorrectly or too often, you may experience damage to your skin or eyes.

Immediate results are possible in some cases, but it can often take weeks or months before you see improvements.

At-home red light therapy devices are also safe, but they are not as powerful as professional instruments. The quality of devices varies, and some machines may not produce the benefits you expect. Clinical treatments with a trained provider may offer greater assurance of effective results with little to no side effects. However, this may require more frequent visits.

People with sensitive skin or diabetes should ask their healthcare provider before trying this therapy. Pregnant women should also seek their healthcare provider's advice.

Treatment Alternatives

Many of the human studies involving red light therapy used small sample sizes, so more research is needed to confirm safety and effectiveness. Your healthcare provider or therapist can suggest other nonmedical treatments to manage your conditions.

Options include:

  • Anti-inflammatory diet: Certain foods can help lower or prevent chronic inflammation, which triggers many illnesses.
  • Cognitive behavioral therapy (CBT): CBT, a type of psychotherapy, or talk therapy, is a well-documented method of treating mental health illnesses such as anxiety and depression.
  • Cupping therapy: This ancient practice also stimulates blood flow, which may help relieve inflammation and psychiatric conditions.
  • Acupuncture: Acupuncture shows potential to help reduce chronic pain, improve skin appearance, and aid with mental health.

Costs and Insurance

Red light therapy can cost $25–$200 or more per session. Prices depend on the location of the service and the specific type of procedure. Keep in mind that treatments are needed approximately every three weeks and may continue for months.

At-home devices range from $149 to thousands of dollars.

Currently, most insurance policies do not cover red light therapy. Some dermatologists may offer this service, however. Your insurance plan can provide guidance on cost factors and the benefits available to you.

Summary

Red light therapy is a noninvasive treatment that uses red or near-infrared light to help heal muscles, skin, or other parts of your body. It is also called photobiomodulation, low-level laser therapy, and other terms.

Red light therapy exposes you to low levels of laser or LED-generated light which penetrates skin or muscle. Unlike UV light, this type does not make heat or burn the skin.

The treatment may also help fight oxidative stress (imbalance between antioxidant and free radical compounds in the body) and lower inflammatory responses within the cells. It may help with conditions such as muscle strain, dental problems, aging skin, and cognitive decline.

Red light therapy should not cause pain or burn your skin. If you experience any irritation, please discontinue use and consult a healthcare provider.

A Word From Verywell

Red light therapy can be an affordable, nonmedical method for improving many conditions that may not respond to conventional treatments alone. It is safe for most people.

A healthcare provider can give you a proper diagnosis of any condition that you want to treat with this procedure. They can also point you to alternatives known to be effective. Make sure your practitioner has credentials and an established reputation for performing red light therapy. If purchasing an at-home device, research your options carefully.

Frequently Asked Questions

  • How much weight can you lose with red light therapy?

    There is little evidence of potential for weight loss with red light therapy. Most research focuses on weight circumference reductions. Limited studies suggest that this treatment may cause fat cells to shrink, but these studies may be biased since they were funded by device manufacturers.

  • What does red light do to your brain?

    Red light can deliver light particles to the brain that stimulate mitochondria there. This may encourage blood flow and help lower inflammation in the brain. It can also help the brain create new nerve cells.

  • Does red light therapy work on spider veins?

    Evidence is scarce that red light therapy may help reduce spider veins when used as part of photodynamic therapy.

  • Can you use red light therapy everyday?

    Currently, it is not known how often you can use red light therapy for specific conditions. Everyday use may be safe in some cases, though. Ask your healthcare provider about the best frequency for you.

  • Does red light stimulate collagen?

    Red light exposure can help increase collagen production. In a 2014 study, participants had more collagen density after treatment. Research states that cells involved with collagen production can be stimulated with the wavelengths the red light provides.

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30 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Leyane TS, Jere SW, Houreld NN. Cellular signalling and photobiomodulation in chronic wound repairInternational Journal of Molecular Sciences. 2021;22(20):11223. doi:10.3390/ijms222011223

  2. Genome.gov. Mitochondria.

  3. de Freitas LF, Hamblin MR. Proposed mechanisms of photobiomodulation or low-level light therapyIEEE J Select Topics Quantum Electron. 2016;22(3):348-364. doi:10.1109/JSTQE.2016.2561201

  4. Ablon G. Phototherapy with light emitting diodesJ Clin Aesthet Dermatol. 2018;11(2):21-27.

  5. Avci P, Gupta A, Sadasivam M, et al. Low-level laser (Light) therapy (Lllt) in skin: stimulating, healing, restoringSemin Cutan Med Surg. 2013;32(1):41-52.

  6. Egger A, Resnik SR, Aickara D, et al. Examining the safety and efficacy of low-level laser therapy for male and female pattern hair loss: a review of the literature. Skin Appendage Disord. 2020;6(5):259-267. doi:10.1159/000509001

  7. Leyane TS, Jere SW, Houreld NN. Cellular signalling and photobiomodulation in chronic wound repairInternational Journal of Molecular Sciences. 2021;22(20):11223. doi:10.1097/MD.0000000000014391

  8. Sousa DFM de, Gonçalves MLL, Politti F, et al. Photobiomodulation with simultaneous use of red and infrared light emitting diodes in the treatment of temporomandibular disorder: study protocol for a randomized, controlled and double-blind clinical trialMedicine. 2019;98(6):e14391. doi:10.1097/MD.0000000000014391

  9. de Freitas L, Calixto G, Chorilli M, et al. Polymeric nanoparticle-based photodynamic therapy for chronic periodontitis in vivoIJMS. 2016;17(5):769. doi:10.3390/ijms17050769

  10. Sikora M. The efficacy of low-level laser therapy in burning mouth syndrome – a pilot studyACC. 2018;57(2). doi:10.20471/acc.2018.57.02.12

  11. Bardellini E, Veneri F, Amadori F, Conti G, Majorana A. Photobiomodulation therapy for the management of recurrent aphthous stomatitis in children: clinical effectiveness and parental satisfactionMed Oral. Published online 2020:e549-e553. doi:10.4317/medoral.23573

  12. Hamblin MR, Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulationAIMSBPOA. 2017;4(3):337-361. doi:10.3934%2Fbiophy.2017.3.337

  13. Chow R, Liebert A, Tilley S, Bennett G, Gabel CP, Laakso L. Guidelines versus evidence: what we can learn from the Australian guideline for low-level laser therapy in knee osteoarthritis? A narrative reviewLasers Med Sci. 2021;36(2):249-258. doi:10.1007/s10103-020-03112-0

  14. Tomazoni SS, Machado C dos SM, De Marchi T, et al. Infrared low-level laser therapy (Photobiomodulation therapy) before intense progressive running test of high-level soccer players: effects on functional, muscle damage, inflammatory, and oxidative stress markers—a randomized controlled trialOxidative Medicine and Cellular Longevity. 2019;2019:e6239058. doi:10.1155/2019/6239058

  15. Zhang P, Wu MX. A clinical review of phototherapy for psoriasisLasers Med Sci. 2018;33(1):173-180. doi:10.1007/s10103-017-2360-1

  16. Ezzati K, Laakso EL, Saberi A, Yousefzadeh Chabok S, Nasiri E, Bakhshayesh Eghbali B. A comparative study of the dose-dependent effects of low level and high intensity photobiomodulation (laser) therapy on pain and electrophysiological parameters in patients with carpal tunnel syndrome. Eur J Phys Rehabil Med. 2020 Dec;56(6):733-740. doi:10.23736/S1973-9087.19.05835-0.

  17. Chi CC, Wang SH, Delamere FM, Wojnarowska F, Peters MC, Kanjirath PP. Interventions for prevention of herpes simplex labialis (Cold sores on the lips). Cochrane Skin Group, ed. Cochrane Database of Systematic Reviews. doi:10.1002/14651858.cd010095.pub2

  18. Huang N, Yao D, Jiang W, et al. Safety and efficacy of 630-nm red light on cognitive function in older adults with mild to moderate alzheimer’s disease: protocol for a randomized controlled studyFront Aging Neurosci. 2020;0. doi:10.3389/fnagi.2020.00143

  19. Maiello M, Losiewicz OM, Bui E, et al. Transcranial photobiomodulation with near-infrared light for generalized anxiety disorder: a pilot studyPhotobiomodulation, Photomedicine, and Laser Surgery. 2019;37(10):644-650. doi:10.1089/photob.2019.4677

  20. Nussbaumer-Streit B, Forneris CA, Morgan LC, et al. Light therapy for preventing seasonal affective disorder. Cochrane Database Syst Rev. 2019;3(3):CD011269. doi:10.1002/14651858.CD011269.pub3

  21. Caruso-Davis MK, Guillot TS, Podichetty VK, et al. Efficacy of low-level laser therapy for body contouring and spot fat reductionOBES SURG. 2011;21(6):722-729. doi:10.1007/s11695-010-0126-y

  22. Tomazoni SS, Almeida MO, Bjordal JM, et al. Photobiomodulation therapy does not decrease pain and disability in people with non-specific low back pain: a systematic reviewJournal of Physiotherapy. 2020;66(3):155-165. doi:10.1016/j.jphys.2020.06.010

  23. Klausner G, Bensadoun RJ, Champion A, et al. État de l’art de la photobiomodulation dans la prise en charge des effets secondaires de la radiothérapie : indications et niveaux de preuveCancer/Radiothérapie. 2021;25(6-7):584-592. doi:10.1016/j.canrad.2021.06.025

  24. Hulander E, Bärebring L, Turesson Wadell A, et al. Proposed anti-inflammatory diet reduces inflammation in compliant, weight-stable patients with rheumatoid arthritis in a randomized controlled crossover trialThe Journal of Nutrition. 2021;151(12):3856-3864. doi: 10.1093/jn/nxab313

  25. Ghahari S, Mohammadi-Hasel K, Malakouti S, Roshanpajouh M. Mindfulness-based cognitive therapy for generalised anxiety disorder: a systematic review and meta-analysisEast Asian Arch Psychiatry. 2020;30(2):52-56. doi:10.12809/eaap1885

  26. Choi TY, Ang L, Ku B, Jun JH, Lee MS. Evidence map of cupping therapyJCM. 2021;10(8):1750. doi:10.3390/jcm10081750

  27. Choi TY, Ang L, Ku B, Jun JH, Lee MS. Evidence map of cupping therapy. JCM. 2021;10(8):1750. doi:10.1016/j.jpain.2017.11.005

  28. Platinum LED Therapy Lights. How much does red light therapy cost?.

  29. Hamblin MR. Shining light on the head: Photobiomodulation for brain disordersBBA Clinical. 2016;6:113-124.doi.org:10.1016/j.bbacli.2016.09.002

  30. Wunsch A, Matuschka K. A controlled trial to determine the efficacy of red and near-infrared light treatment in patient satisfaction, reduction of fine lines, wrinkles, skin roughness, and intradermal collagen density increasePhotomedicine and Laser Surgery. 2014;32(2):93-100.doi:10.1089/pho.2013.3616