1. Principle of Red Light Therapy
Red light therapy (RLT) uses specific wavelengths of visible red light (600–700 nm) and near-infrared light (700–1,100 nm) to stimulate cell mitochondria through photobiomodulation (PBM). This produces the following key reactions:
Mitochondrial activation:
Red light and near-infrared light (NIR) are absorbed by cytochrome c oxidase (a key mitochondrial enzyme) in cells, promoting adenosine triphosphate (ATP) synthesis and enhancing the capabilities of cells to repair and regenerate.
- Antioxidant and anti-inflammatory
It reduces reactive oxygen species (ROS) and oxidative stress.
It inhibits pro-inflammatory factors (such as TNF-α and IL-6) and relieves chronic inflammation.
Microcirculation is improved.
It promotes the release of nitric oxide (NO), dilates blood vessels and increases blood flow.
Increase collagen and elastin synthesis.
Red light (especially at 660 nm) stimulates fibroblasts directly and promotes collagen regeneration.
2. The main effects of red light therapy
1. Skin health and anti-ageing
Reduces wrinkles and fine lines by stimulating collagen production (clinical studies show an increase of 30–40%).
- Improve acne and acne scars: 660 nm red light inhibits Propionibacterium acnes and reduces inflammation.
Repair light damage by reducing pigmentation and erythema caused by ultraviolet rays.
2. Pain management and sports recovery:
Relieve muscle soreness (DOMS): 850 nm near-infrared light penetrates deep into the tissues, accelerating the clearance of lactic acid (studies show that recovery time is shortened by 50%).
Reduce arthritis and joint pain: improve mobility by reducing joint synovitis (studies show a 40–60% reduction in pain in patients with knee arthritis).
3. Wound healing and tissue repair:
Accelerate wound healing, including for diabetic foot ulcers and postoperative wounds (healing speed increased twofold in clinical trials).
Scar reduction: inhibits excessive fibrosis and promotes normal tissue regeneration.
4. Other potential benefits:
Improve hair loss: Stimulate hair follicle stem cells using 650 nm red light for androgenic alopecia.
Neuroprotection: Near infrared light (810 nm) may improve brain function, as demonstrated in studies on Alzheimer’s disease and stroke.
Sleep and mood regulation: This is achieved by regulating melatonin and serotonin levels.
三、The difference in application between red light and near-infrared light.
| Wavelength | Penetration depth | Best application scenarios |
|---|---|---|
| 660nm red light | 1–5 mm | Anti-aging, acne, epidermal repair |
| 850nm near-infrared | 5–10 cm | Muscle pain, deep arthritis, brain health |
| Dual wavelength combination | Full coverage | Comprehensive anti-aging + deep repair (recommended first choice) |
Summary: Red light therapy is a non-invasive, painless and side-effect-free form of physical therapy suitable for skin repair, pain management and improving overall health.