How Does Red Light Therapy Work?
It all began in outer space.
In the 1990s, while scientists were experimenting with red LED lights1 to grow plants for space shuttle missions, they noticed that their skin lesions began to heal faster with exposure to the light. [1, 2]
Fast-forward 30ish years, and the cosmetic and wellness industries have fully embraced red light therapy’s benefits. Lamps, masks, and wands straight out of the Star Wars movies flood the market, Instagram, and TikTok (and incredible before/after photos and videos to boot).
Celebrity biohackers and scientists such as Andrew Huberman and Gary Brecka have praised it for its wondrous health applications in several fields, including ophthalmology2, pain, cognition, and, most popularly, dermatology.
What’s the hype behind the buzz? Well, it’s not rocket science — red light therapy comes with some pretty great, proven benefits. As we outline those benefits, while also encouraging readers to understand about potential long-term side effects if products are not used as intended.
So, what’s the hype about? Are its benefits purely anecdotal, or is there a scientific basis for it? In this article, we’ll cover:
- What red light therapy is.
- How red light therapy works.
- Benefits of red light therapy.
- How long it takes red light therapy to work.
- How infrared saunas use red light therapy.
So, what is red light therapy?
Red light therapy uses low-power red or near-infrared light to promote healing, reduce inflammation, and stimulate cell regeneration. This therapy typically involves devices emitting red light wavelengths between 630 and 700 nanometers or near-infrared wavelengths between 800 and 900 nanometers. [3]
How does red light therapy work?
Source: Visible Red Light Emitting Diode Photobiomodulation for Skin Fibrosis: Key Molecular Pathways4
Red light therapy devices send concentrated wavelengths of red and near-infrared light deep into the layers of our skin. The photons then interact with and stimulate biological tissue, a process called photobiomodulation (PBM). [4]
This kicks off several mechanisms, including two important ones:
Absorption by Cytochrome C Oxidase
Cytochrome c oxidase (CCO) is an enzyme found inside the mitochondria (which you might remember from high school biology class, is called the “powerhouse of the cell.”) It contains chromophores (light-absorbing molecules) like heme and copper, which readily absorb red and near-infrared light photons. This amps up the synthesis of adenosine triphosphate (ATP), the primary energy currency of cells. This then fuels various cellular processes, including tissue repair and regeneration.
Nitric Oxide (NO) Release
PBM can trigger the release of nitric oxide (NO) from the mitochondria. [5] NO is crucial to several bodily processes, including the skin’s response to several stimuli, such as UV exposure, heat, infection, and inflammation. [6] This has a ripple effect, contributing to improving:
- Blood vessel health
- Wound healing
- Pain management
- Collagen synthesis
Red Light Therapy Benefits
The processes red light therapy activates in the body lead to great benefits across various aspects of health. Here's what you can look forward to:
Red light therapy for skin
Red light therapy helps calm and decrease redness while minimizing oil production and bacteria on the skin. In a study done in 2018 [11], researchers confirmed the benefits of red light therapy in treating mild to moderate acne because of its anti-inflammatory properties.
Pain and inflammation
Remember the ton of nitric oxide that PBM releases? Because of its impact on blood circulation, it enables blood vessels to deliver vital nutrients and oxygen to damaged tissues more effectively, aiding their repair and regeneration. Studies have demonstrated its role in reducing persistent inflammatory pain [12]
Wound healing
Red light therapy has been shown to have positive effects on wound healing, with animal studies reporting improvements in wound repair and pain relief in under a month.[13] [14]
Improved athletic recovery time
A 2018 study by Brazilian researchers found that after their trial on pro soccer players, those who underwent red light therapy stayed longer on the playing field. They concluded that red light therapy significantly improved all the biochemical markers evaluated and that pre-exercise light therapy can enhance performance and accelerate recovery. [15]
Hair loss
Red light therapy, specifically low-level laser therapy (LLLT), has shown promising results in treating hair loss in both males [16] and females [17]. It has also been found to be a safe and well-tolerated treatment for telogen effluvium, a type of hair loss often associated with long COVID. [18].
How Long Before You’ll See Effects From Red Light Therapy?
Much research for different red light therapy applications is based on trials that include daily or weekly of about 15-30 minutes for several weeks or months. Although the mechanisms of PBM are activated immediately, different conditions take different amounts of time to produce the desired results.
For instance, acne and wound healing could take a couple of weeks, but conditions like hair loss and cellulite management may take months.
Infrared Saunas vs Red Light Therapy
Is using a red light therapy device the same as sitting in an infrared sauna? They both use light, right? Not entirely.
The main difference is that red light therapy gives off light, while infrared saunas give off light and heat. There is zero heat involved with red light therapy — the LED lights themselves don’t get hot, and you won’t profusely sweat or experience a high heart rate, like what you’d experience sitting in an infrared or traditional sauna.
How Does an Infrared Sauna Work?
Infrared saunas work by emitting infrared radiation, which has both direct and indirect effects on cells and tissues by changing cell signaling and metabolism.
Besides chromophores like CCO, infrared radiation also affects water in cells, which can change cell membrane properties and signaling pathways. This interaction can increase the production of reactive oxygen species (ROS), alter ATP production, and change calcium and nitric oxide levels in cells. These changes can trigger stress responses, metabolic processes, and cell growth and development changes that lead to the many benefits of infrared saunas, such as improving lung capacity, heart health, and neurocognitive diseases.[19]
Red light therapy at Sauna House
Want to try red light therapy for yourself? Enjoy our private Hot, Cold, Relax rooms which include a traditional sauna, cold plunge, and two red light therapy panels in each. Book your visit today.
Citing our sources
1. Cotler HB. A NASA discovery has current applications in Orthopaedics. Curr Orthop Pract. 2015 Jan;26(1):72-74. doi: 10.1097/BCO.0000000000000196. PMID: 25541589; PMCID: PMC4272231.
2. Salzano AD, Khanal S, Cheung NL, et al. Repeated Low-level Red-light Therapy: The Next Wave in Myopia Management?. Optom Vis Sci. 2023;100(12):812-822. doi:10.1097/OPX.0000000000002083 |
3. Yadav A, Gupta A. Noninvasive red and near-infrared wavelength-induced photobiomodulation: promoting impaired cutaneous wound healing. Photodermatology, Photoimmunology & Photomedicine. 2017;33(1):4-13. doi:10.1111/phpp.12282 | https://pubmed.ncbi.nlm.nih.gov/27943458/
4. Mamalis, Andrew & Siegel, Daniel & Jagdeo, Jared. (2016). Visible Red Light Emitting Diode Photobiomodulation for Skin Fibrosis: Key Molecular Pathways. Current Dermatology Reports. 5. 10.1007/s13671-016-0141-x.
5. Quirk BJ, Whelan HT. What Lies at the Heart of Photobiomodulation: Light, Cytochrome C Oxidase, and Nitric Oxide-Review of the Evidence. Photobiomodul Photomed Laser Surg. 2020 Jul 21;38(9):527–30. doi:
10.1089/photob.2020.4905. Epub ahead of print. PMID: 32716711; PMCID: PMC7495914. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7495914/
6. Suschek CV, Feibel D, von Kohout M, Opländer C. Enhancement of Nitric Oxide Bioavailability by Modulation of Cutaneous Nitric Oxide Stores. Biomedicines. 2022; 10(9):2124. doi: 10.3390/biomedicines10092124 | https://www.mdpi.com/2227-9059/10/9/2124
7. Richard O Cannon, Role of nitric oxide in cardiovascular disease: focus on the endothelium, Clinical Chemistry, Volume 44, Issue 8, 1 August 1998, Pages 1809–1819, https://doi.org/10.1093/clinchem/44.8.1809
8. Witte MB, Barbul A. Role of nitric oxide in wound repair. Am J Surg. 2002;183(4):406-412. doi:10.1016/s0002-9610(02)00815-2
9. Cury Y, Picolo G, Gutierrez VP, Ferreira SH. Pain and analgesia: The dual effect of nitric oxide in the nociceptive system. Nitric Oxide. 2011;25(3):243-254. doi:10.1016/j.niox.2011.06.004
10. Xia W, Szomor Z, Wang Y, Murrell GA. Nitric oxide enhances collagen synthesis in cultured human tendon cells. J Orthop Res. 2006;24(2):159-172. doi:10.1002/jor.20060
11. Miller D, Cohen MJ, Adenaike A, Fitzgerald L, Biron J, Gold MH. Commercial support: Johnson & Johnson. J Am Acad Dermatol. 2018. doi:10.1016/j.jaad.2018.05.1175. © 2018 Published by Elsevier Inc.
12. Martins DF, Turnes BL, Cidral-Filho FJ, Bobinski F, Rosas RF, Danielski LG, Petronilho F, Santos ARS. Light-emitting diode therapy reduces persistent inflammatory pain: Role of interleukin 10 and antioxidant enzymes. Neuroscience. 2016. doi:10.1016/j.neuroscience.2016.03.035.
13. Li Y, Zhang J, Xu Y, et al. The histopathological investigation of red and blue light emitting diode on treating skin wounds in Japanese Big-Ear White Rabbit. PLoS One. 2016;11(6):e0157898. doi:10.1371/journal.pone.0157898.
14. Cheon MW, Kim TG, Lee YS, et al. Low level light therapy by Red–Green–Blue LEDs improves healing in an excision model of Sprague–Dawley rats. Pers Ubiquit Comput. 2013;17:1421-1428. doi:10.1007/s00779-012-0577-3.
15. De Marchi T, Leal-Junior ECP, Lando KC, et al. Photobiomodulation therapy before futsal matches improves the staying time of athletes in the court and accelerates post-exercise recovery. Lasers Med Sci. 2019;34(1):139-148. doi:10.1007/s10103-018-2643-1
16, 17. Lanzafame, Raymond & Blanche, Raymond & Bodian, Adam & Chiacchierini, Richard & Fernandez-Obregon, Adolfo & Kazmirek, Eric. (2013). The Growth of Human Scalp Hair Mediated by Visible Red Light Laser and LED Sources in Males. Lasers in surgery and medicine. 45. 487-95.
18. Gerkowicz A, Bartosińska J, Krakowski P, et al. Red LED light therapy for telogen effluvium in the course of long COVID in patients with and without androgenetic alopecia. Ann Agric Environ Med. 2024. doi:10.26444/aaem/177238.
19. Sandell J, Davies M. Benefits of sauna on lung capacity, neurocognitive diseases, and heart health. World J Adv Res Rev. 2023;17(1):57-62. doi:10.30574/wjarr.2023.17.1.1414.
