What Is Red Light Therapy?
Skin Health, Sleep, and Recovery: Claimed Benefits
Muscle Recovery and Performance
Scientific Evidence and Clinical Studies
Commercial Growth: Devices and Startups
Limitations and Future Research
Glowing Promises, Mixed Results
Can shining a red light on your skin improve your sleep, heal your muscles, and make you look younger? Red light therapy (RLT), once confined to medical clinics and elite sports facilities, is now a booming industry, promising benefits that sound almost too good to be true. But does the science support these claims, or is it just another wellness trend?
Red light therapy, also known as low-level laser therapy (LLLT), utilizes low-level red or near-infrared light to stimulate cellular function and tissue healing. Originally researched by NASA to enhance plant growth and accelerate wound healing in astronauts, RLT has since been explored for multiple medical applications.1
In dermatology, RLT is recognized for its potential to improve skin health by reducing wrinkles, scars, and acne through collagen stimulation and increased blood circulation. Additionally, it may aid in wound healing and alleviate inflammation associated with conditions such as osteoarthritis and tendinitis.2
However, the scientific evidence supporting these claims varies, requiring a critical evaluation of its effectiveness and the need to distinguish between medically approved devices and over-the-counter consumer products.
This article assesses the current research, mechanisms of action, and commercial growth of RLT while identifying its limitations and future research directions.
Image Credit: Dikushin Dmitry/Shutterstock.com
What Is Red Light Therapy?
Red light therapy utilizes specific wavelengths of red and near-infrared light, typically in the 600–1000 nm range, to stimulate cellular activity without producing heat.
The biological mechanism behind RLT involves the absorption of light by mitochondria, particularly by cytochrome c oxidase, a key enzyme in cellular respiration. This absorption enhances adenosine triphosphate (ATP) production, increasing cellular energy and promoting repair and regeneration.3
Additionally, red light stimulates the release of reactive oxygen species at controlled levels, triggering anti-inflammatory and antioxidant responses. It also improves blood flow by stimulating nitric oxide production, facilitating oxygen and nutrient delivery to damaged tissues.
These combined effects are believed to accelerate wound healing, reduce inflammation, enhance collagen production, and support muscle recovery, making RLT a promising therapy for a range of medical and cosmetic applications.3
These physiological responses have been explored for various medical and cosmetic applications, ranging from wound healing and pain relief to skin rejuvenation and sleep enhancement.4
Medical-grade red light therapy devices, such as high-powered light-emitting diode (LED) panels and laser-based systems, are used in clinical settings to treat wounds, reduce inflammation, and promote skin rejuvenation. These devices deliver precise wavelengths and higher intensities, ensuring deeper tissue penetration.5
In contrast, at-home consumer products, including consumer-grade LED panels, handheld devices, face masks, and light therapy beds, offer lower-intensity treatments designed for general wellness, anti-aging, and muscle recovery.6
Furthermore, while medical-grade devices are often Food and Drug Administration (FDA)-approved and used under professional supervision, consumer versions provide convenience but frequently lack standardized dosing parameters and may require longer treatment times for noticeable results.5
5 Biohacking Secrets to Help You Live Longer
Skin Health, Sleep, and Recovery: Claimed Benefits
Skin Health
Red light therapy has been extensively studied in dermatology for its role in promoting collagen synthesis, accelerating wound healing, and reducing inflammation.
Clinical research suggests that RLT can improve skin elasticity, reduce fine lines, and aid in the management of inflammatory conditions such as acne and psoriasis.7 It is believed to stimulate fibroblast activity, enhance extracellular matrix production, and improve skin texture and tone.3
Additionally, RLT has shown efficacy in treating hyperpigmentation disorders, including melasma and vitiligo, by modulating melanocyte activity and reducing oxidative damage.4
However, while some studies confirm its benefits for skin rejuvenation, the variability in treatment protocols highlights the need for standardized guidelines in cosmetic dermatology.8
Sleep Improvement
Research on RLT’s effects on sleep quality suggests that exposure to specific wavelengths can influence circadian rhythms and melatonin secretion.
Photobiomodulation or light therapy, including the use of red wavelengths, has been investigated for its potential to enhance sleep onset, duration, and overall sleep efficiency. Some studies report that RLT exposure before bedtime may reduce sleep latency and improve deep sleep phases by modulating the body's natural light-response mechanisms.9
However, results remain mixed, with some trials showing minimal effects, likely due to differences in exposure timing and individual variability in light sensitivity.
The current evidence suggests that while the theoretical basis for RLT's role in sleep regulation is compelling, further large-scale studies are required to establish optimal application protocols.
Muscle Recovery and Performance
Sports medicine is a field where RLT has gained substantial attention for its potential to reduce muscle fatigue, enhance post-exercise recovery, and improve athletic performance.
Several clinical trials indicate that pre-exercise RLT may increase muscular endurance, reduce delayed-onset muscle soreness, and accelerate recovery through its anti-inflammatory and antioxidant effects.10
Photobiomodulation has also been linked to reduced levels of muscle damage markers such as creatine kinase and lactate dehydrogenase, suggesting a protective effect against exercise-induced oxidative stress.6
However, while some studies support these findings, others report inconsistent results, emphasizing the need for standardized treatment parameters to optimize performance enhancement and recovery benefits.
The Link Between Cortisol, Inflammation, and Disease
Scientific Evidence and Clinical Studies
The scientific literature on RLT presents both promising and conflicting findings across different applications. For skin health, multiple studies confirm its efficacy in enhancing collagen production, improving wound healing, and reducing inflammation.7
Moreover, in clinical settings, RLT has demonstrated effectiveness in treating conditions such as acne vulgaris, rosacea, and eczema, with significant reductions in inflammatory cytokine levels.4
However, in the field of sleep quality improvement, although some controlled trials suggest that red light exposure may positively impact melatonin regulation and sleep quality, the evidence remains inconclusive.
Variations in study designs, exposure durations, and participant demographics are likely contributors to the inconsistency in reported outcomes.9
Nonetheless, systematic reviews and meta-analyses on the efficacy of RLT in sports therapy support the notion that RLT enhances muscle recovery and reduces oxidative stress.
However, discrepancies in study methodologies, including differences in light wavelengths, intensity, and application timing, pose challenges in establishing universal recommendations.10
Commercial Growth: Devices and Startups
The commercialization of RLT has surged in recent years, with a growing market for both professional-grade and consumer-friendly devices.
The early partnership between NASA and Quantum Devices resulted in the development of WARP (Warfighter Accelerated Recovery by Photobiomodulation), which was approved by the FDA to treat pain, muscle spasms, and inflammation in military personnel.1
More recently, companies such as NovoTHOR are developing red light therapy beds to treat chronic pain and improve circulation.11
Even well-known cosmetic brands such as Dior have paired up with companies that build lighting, such as Lucibel, to develop LED face masks to reverse skin aging.12
Limitations and Future Research
Despite its potential, RLT faces several limitations that warrant further investigation. One primary challenge is the lack of standardized treatment protocols, leading to inconsistencies in study outcomes.
Factors such as optimal wavelength selection, light intensity, and duration of exposure need to be refined to maximize therapeutic benefits.8
Additionally, long-term safety data on repeated RLT exposure remain limited, particularly regarding potential adverse effects on cellular function.
Moreover, while preliminary evidence supports RLT’s role in various health applications, large-scale randomized controlled trials are needed to confirm its efficacy and establish clinical guidelines.
5 Simple Habits for Deeper, More Restful Sleep
Glowing Promises, Mixed Results
In summary, red light therapy represents a promising, non-invasive modality for improving skin health, sleep quality, and muscle recovery.
While existing scientific evidence supports several of its claims, inconsistencies in study findings highlight the need for standardized treatment protocols and further clinical validation.
As RLT continues to expand in both clinical and consumer markets, it is crucial to distinguish between medical-grade applications and unverified marketing claims.
Future research should focus on optimizing treatment parameters, assessing long-term safety, and exploring novel therapeutic applications of photobiomodulation.
The molecular mechanisms underlying RLT’s effects on different tissue types, as well as its potential applications in neurodegenerative conditions, immune modulation, and metabolic health, also warrant further investigation.
References
- NASA. (2022, May 19). NASA Research Illuminates Medical Uses of Light | NASA Spinoff. Spinoff.nasa.gov. Available at: https://spinoff.nasa.gov/NASA-Research-Illuminates-Medical-Uses-of-Light [Accessed on March 27, 2025]
- Cleveland Clinic. (2021, December 1). Red Light Therapy: Benefits, Side Effects & Uses. Cleveland Clinic. Available at: https://my.clevelandclinic.org/health/articles/22114-red-light-therapy [Accessed on March 27, 2025]
- Avci, P., Gupta, A., Sadasivam, M., Vecchio, D., Pam, Z., Pam, N., & Hamblin, M. R. (2013). Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring. Seminars in cutaneous medicine and surgery, 32(1), 41–52.
- Glass G. E. (2023). Photobiomodulation: A Systematic Review of the Oncologic Safety of Low-Level Light Therapy for Aesthetic Skin Rejuvenation. Aesthetic surgery journal, 43(5), NP357–NP371. https://doi.org/10.1093/asj/sjad018
- Heiskanen, V., & Hamblin, M. R. (2018). Photobiomodulation: lasers vs. light emitting diodes?. Photochemical & photobiological, 17(8), 1003–1017. https://doi.org/10.1039/c8pp90049c
- Romano, G., Insero, G., Marrugat, S. N., & Fusi, F. (2022). Innovative light sources for phototherapy. Biomolecular concepts, 13(1), 256–271. https://doi.org/10.1515/bmc-2022-0020
- Dębiec, P., Roman, J., Gondko, D., & Pietrzak, N. (2024). Clinical Applications of Phototherapy in Treating Skin Disorders. Journal of education, health and sport, 73, 51693. https://doi.org/10.12775/jehs.2024.73.51693
- Borrelli, E., Coco, G., Pellegrini, M., Mura, M., Ciarmatori, N., Scorcia, V., Carnevali, A., Lucisano, A., Borselli, M., Rossi, C., Reibaldi, M., Ricardi, F., Vagge, A., Nicolò, M., Forte, P., Cartabellotta, A., Hasanreisoğlu, M., Kesim, C., Demirel, S., Yanık, Ö., … Giannaccare, G. (2024). Safety, Tolerability, and Short-Term Efficacy of Low-Level Light Therapy for Dry Age-Related Macular Degeneration. Ophthalmology and therapy, 13(11), 2855–2868. https://doi.org/10.1007/s40123-024-01030-w
- Chambe, J., Reynaud, E., Maruani, J., Fraih, E., Geoffroy, P. A., & Bourgin, P. (2023). Light therapy in insomnia disorder: A systematic review and meta-analysis. Journal of sleep research, 32(6), e13895. https://doi.org/10.1111/jsr.13895
- Luo, W. T., Lee, C. J., Tam, K. W., & Huang, T. W. (2022). Effects of Low-Level Laser Therapy on Muscular Performance and Soreness Recovery in Athletes: A Meta-analysis of Randomized Controlled Trials. Sports health, 14(5), 687–693. https://doi.org/10.1177/19417381211039766
- Fitzmaurice, B., Heneghan, N. R., Rayen, A., & Soundy, A. (2022). Whole-body photobiomodulation therapy for chronic pain: a protocol for a feasibility trial. BMJ open, 12(6), e060058. https://doi.org/10.1136/bmjopen-2021-060058
- Couturaud, V., Le Fur, M., Pelletier, M., & Granotier, F. (2023). Reverse skin aging signs by red light photobiomodulation. Skin research and technology, 29(7), e13391. https://doi.org/10.1111/srt.13391
Further Reading