670 nm
Biological mechanism
Red light: mitochondrial activation
Cytochrome c oxidase absorbs 670 nm light, increasing ATP synthesis and reducing oxidative stress. This drives wound healing, skin rejuvenation, and retinal protection.
Penetration depth: ~3.2 mm
Tissue layers: epidermis · dermis · subcutaneous
Absorption: low (therapeutic)
Clinical evidence by area
Skin aging
Clinical
Collagen synthesis, wrinkle reduction
Wound healing
Clinical
Enhanced tissue repair, reduced erythema
Retinal health
Early research
Cockcroft-ATP in photoreceptors
Muscle recovery
Clinical
Reduced soreness, faster regeneration
Hair growth
Early research
follicle stimulation, increased density
Brain / cognition
Clinical
Increased prefrontal oxygen, memory
Joint pain
Clinical
Reduced osteoarthritis scores
Metabolic
Early research
Blood glucose modulation, thyroid
Exploring red-light therapy · wavelength 670 nm