Photobiomodulation (Red & Near-Infrared Light)

What it is

Photobiomodulation (PBM), also called low-level laser therapy (LLLT), delivers red (~630–700 nm) and near-infrared (~810–1064 nm) light to tissue at non-thermal intensities. The proposed primary photoacceptor is cytochrome c oxidase (complex IV) in mitochondria.

Claimed effects

• Improved mitochondrial respiration and ATP output.
• Reduced inflammation.
• Accelerated wound healing.
• Possible benefit in dry age-related macular degeneration (LIGHTSITE trials).
• Skin (collagen, photoaging) effects with home red-light panels.

Evidence summary

Mixed. Wound-healing and certain musculoskeletal indications have reasonable evidence. Many longevity-marketed claims (cognitive enhancement, fat loss, hair growth) have weak or inconsistent RCT support. Dose–response is biphasic (the “Arndt-Schulz” curve) — under- and over-dosing both reduce benefit.

Practical points

• Home red-light panels vary wildly in irradiance (mW/cm²) and effective dose. Spec sheets are inconsistent.
• Eye protection at high near-infrared output.
• Sessions on the order of 10–20 minutes are typical.

Related entries

Mitochondrial dysfunction, Age-related macular degeneration.