What is Photobiomodulation (PBM)?
Photobiomodulation (PBM) uses visible red and near-infrared (NIR) light to stimulate cellular processes. It is non-thermal and non-ionizing. Primary targets include cytochrome c oxidase in mitochondria. The proposed mechanism, mostly from cell and animal studies, is that this may enhance ATP production and reduce oxidative stress. See the evidence review.
Key Mechanisms
- •Cytochrome c oxidase — absorbs red/NIR, may increase electron transport and ATP
- •Nitric oxide — light can dissociate NO from cytochrome c oxidase, restoring respiration
- •Water viscosity — some models suggest light reduces viscosity around proteins
- •NIR penetration — NIR penetrates deeper than visible red; how much reaches deeper tissue depends on wavelength and dose
Why does photobiomodulation matter?
Photobiomodulation matters because it is one of the few light-based approaches studied as a drug-free way to influence tissue repair, pain, and inflammation. It is used in clinical settings such as supportive care for oral mucositis during cancer treatment, and it is widely sold in consumer red-light devices.
The gap between those two worlds is important. Clinical trials use controlled wavelengths, power densities, and exposure times, while many home devices publish little of that information. Overall, the evidence is mixed: some uses have reasonable support, while claims about skin aging, fat loss, cognition, or athletic recovery remain uncertain or rest on small studies.
What affects photobiomodulation?
Dose is the biggest factor, and more light is not necessarily better. Researchers describe a biphasic dose response, where too little light has no effect and too much can cancel the benefit or inhibit cells. Wavelength decides which molecules absorb the light and how deep it travels. Skin pigmentation, hair, tissue thickness, and the distance between the device and the skin change how much light actually reaches the target. Pulsed versus continuous delivery may also matter, although studies disagree. Because trials differ so much in their settings, results are hard to compare, which is a major reason the evidence stays inconsistent.
In ONDA Life
The Mitochondrial DNA Red Light article covers photonic charging protocols using red/NIR panels.