The Science Behind Pulsed Light Therapy
Red light therapy has long been recognised for its incredible skin-rejuvenating benefits. However, not all light therapy is created equal. At Maysama, we believe that pulsed light therapy is the key to taking LED treatments to the next level. But what makes pulsed light so effective, and why should you consider it over continuous wave light?
Our approach is based on our on-going dialogue with leading researchers, together with science papers which support the supreme efficacy of pulsed light photobiomodulation. Let’s dive into the the main effects of pulsed light and the science that supports it.
1. Enhanced Skincare Absorption
It was Maysama’s discussion with leading photobiomodulation scientist, Andrei Sommer, which first brought our attention to the benefits of pulsed LED. Sommer explained how his research team use pulsed light to improve the uptake of anti-cancer drugs, including EGCG from green tea.
Pulsing causes the cell to ‘swell’ and contract repeatedly, creating a "breathing" effect. When the cell contracts it ‘sucks’ in micronutrients surrounding the cell by Transmembrane Convection. When pulsed light is used in combination with your topical skincare, it benefits the uptake of skincare ingredients helping to improve the efficacy of your skincare products.
2. Deeper Light Penetration
Brondon’s research comparing pulsed and continuous light have shown that pulsed light penetrates the skin more deeply. This study concludes that pulsed light could give an advantage to individuals with darker skin tones, as it can better penetrate melanin-rich skin.
3. Reduces Oxidative Stress
A concern with prolonged light therapy is the potential for oxidative stress caused by the buildup of free radicals. When using continuous light, free radicals can accumulate and eventually reduce the efficacy of your treatment. However, Sommer’s 2016 paper illustrates how pulsed light allows for short rest periods between pulses, enabling free radicals to dissipate and minimizing oxidative stress. This extends the effectiveness of your LED device and ensures long-term benefits.
4. Upregulates Production of ATP
ATP is the energy source for cells, playing a crucial role in skin repair and collagen production. Research has shown that pulsed LED light stimulates ATP production more effectively than continuous wave light. Keshri’s in vivo pulsed light studies found that pulsed light at a frequency of 10Hz significantly accelerated wound healing.
More than two and a half thousand women were involved in a study which treated episiotomies (the cut the doctor often gives during the 2nd stage of labour to make the birth easier) with pulsed light. These research studies used pulsed light at various frequencies from 10 to 100Hz, and concluded that pulsed light was more effective than continuous light for healing the wound.
5. Accelerated Cell Proliferation
There are several studies that support that pulsed LED light accelerates cell proliferation more so than its continuous wave counterpart. Ueda & Shimizu demonstrated that pulsed light (1Hz and 8 Hz) is significantly superior to continuous wave when it comes to stimulating cell proliferation and bone formation in vitro. Brondon’s studies with the melanin filters also concluded that cell proliferation was stimulated more by pulsed light.
6. Cells Need Periods of Rest
Cells naturally function in cycles, requiring periods of activity and rest. Hashmi’s review of pulsed light studies suggests that ‘cells may need periods of rest, without which they can no longer be stimulated further’. Research suggests that the improved outcomes when using pulsed light may be due to pulsed light having a similar frequency to natural frequencies, which exist in biological systems. This sounds remarkably like the principles of microcurrent, whereby the success of microcurrent for skin rejuvenation depends largely on the modality mimicking the body’s own electrical currents.
7. Better Collagen Production
Barolet’s recent studies look at the impact of pulsed light parameters on collagen production by fibroblasts. Barolet proposes that the success of specific pulse parameters may be due to their ability to dissociate nitric oxide from cytochrome c oxidase, which then allows oxygen to bind again, driving mitochondrial respiration and ATP production. The irregularity of pulsed light presents the opportunity for multiple trigger events, increasing the beneficial impact of the light stimulus. It’s interesting that Fireflies rely on the same action of NO release and oxygen binding to pulse their light!
Conclusion: The Future of LED Light Therapy
Numerous scientific studies support the superiority of pulsed light over continuous wave photobiomodulation. The key benefits include deeper light penetration, enhanced mitochondrial stimulation, accelerated cell metabolism, increased ATP production, improved collagen synthesis, and better absorption of skincare ingredients.
Inevitably, as with any area of research, findings can vary. While many studies highlight the advantages of pulsed light, some suggest no difference or even instances where continuous light may be more beneficial. This is to be expected because we
see this variation across all studies on photobiomodulation – sometimes studies show no results or conflicting results, yet we manage to draw conclusions on which are the best parameters for wavelengths and dosing. It is no different for pulsed light – whilst researchers do not yet fully understand the mechanisms by which pulsed light influences biostimulation, overall they agree that pulsing has an effect on cells which is beneficial and distinct from continuous wave.
The importance of pulse parameters to optimise outcomes is stressed by Sommer in his 2019 paper. And researchers have successfully interrogated a variety of pulse frequencies with positive outcomes. What is clear is that certain pulse frequency thresholds should not be exceeded to avoid a negative impact on cell viability negatively, as seen in this study.
To harness even greater stimulatory effect from pulsed light, future research may focus further on the definition of pulse parameters, including the duration of dark periods (pause time), as well as pulse intervals. Canadian scientist Barolet is leading the way in this research.
Whatever the future holds, Maysama remains committed to leading the way in pulsed light technology, ensuring our LED devices provide the most effective treatments possible.
Want to learn more? Visit our How It Works page and explore the science behind pulsed LED light therapy today!
Supporting Science Papers
- Sommer – Revisiting the Photon/Cell Interaction Mechanism in Low-Level Light Therapy - PubMed
- Sommer – Laser Modulated Transmembrane Convection: Implementation in Cancer Chemotherapy - ScienceDirect
- Sommer – Tuning the Mitochondrial Rotary Motor with Light - ResearchGate
- Brondon – Pulsing Influences Photoradiation Outcomes in Cell Culture - PubMed
- Keshri – Photobiomodulation with Pulsed and Continuous Wave Near-Infrared Laser (810 nm, Al-Ga-As) Augments Dermal Wound Healing in Immunosuppressed Rats - PLOS One
- Kymplova – Low-Level Light Therapy Study - Liebert Pub
- Ueda – Pulse Irradiation of Low-Power Laser Stimulates Bone Nodule Formation - PubMed
- Miyamoto – Comparison of Phototoxicity Mechanism Between Pulsed and Continuous Wave Irradiation in Photodynamic Therapy - ScienceDirect
- Barolet – Importance of Pulsing Illumination Parameters in Low-Level Light Therapy - PubMed
- Trimmer – Nitric Oxide and the Control of Firefly Flashing - PubMed
- Hashmi – Effect of Pulsing in Low-Level Light Therapy - PMC
- Barolet – Photobiomodulation (PBM) Research - A Comprehensive Database - Google Sheets
- Barolet – Pulsed vs Continuous Wave Low-Level Light Therapy on Osteoarticular Signs and Symptoms in Limited Scleroderma (CREST Syndrome): A Case Report - PubMed
- Plavskii – Effect of Exposure of Sturgeon Roe to Low-Intensity Laser Radiation on the Hardiness of Juvenile Sturgeon - Journal of Applied Spectroscopy
