Pain and physical recovery is the part of the light-therapy literature with the most substance behind it. That does not make it simple. The findings are condition-specific, protocol-specific, and consistently accompanied by caveats about evidence quality — all of which get stripped out by the time a claim reaches a product page.
The Overall Picture
The 2025 umbrella review of photobiomodulation pooled 15 meta-analyses covering 204 randomized controlled trials and more than 9,000 participants across 35 outcomes. Twelve outcomes showed statistically significant effects. Certainty ranged from very low to moderate, and nothing reached high certainty — with moderate-certainty findings reported for outcomes including pain in burning mouth syndrome, knee osteoarthritis disability, fibromyalgia-related fatigue and hair density.
Read that carefully and a rule emerges: the effect sizes are real but modest, and the credible use case is adjunct support inside a broader rehabilitation plan rather than standalone therapy.
Knee Osteoarthritis
A systematic review with meta-analysis on photobiomodulation for pain and disability in knee osteoarthritis found reductions in pain and improvements in disability compared with control conditions. The authors rated certainty as low to very low for important outcomes and cautioned against using PBM as an isolated intervention. For a chronic joint condition where loading, strength and weight management carry the strongest evidence, that caution is the finding, not a footnote to it.
Tendinopathy: The Combination Effect
The most instructive dataset comes from low-level red and near-infrared photobiomodulation for pain and function in tendinopathy — 17 randomized controlled trials with 835 participants. Light combined with exercise outperformed sham plus exercise on pain and function, with variable evidence quality across studies.
The design detail is the lesson. Both groups exercised. The question was never whether light replaces loading; it was whether light adds anything on top of loading. That is the right way to frame every recovery claim in this field.
Skin, Tissue and Scars
A 2026 scoping review of red and near-infrared photobiomodulation for burn, hypertrophic and post-surgical scars identified seven clinical studies involving 297 participants and reported improvements in scar-related outcomes — thickness, pigmentation, elasticity, pain and pruritus — in specific settings, while noting that the studies were small and heterogeneous. Tissue-level applications are where PBM's mechanistic story is most direct, since the light does not have to travel far to reach the target.
Why "Reduces Inflammation" Means Nothing
Inflammation is not one process. Asking whether light reduces inflammation is like asking whether exercise improves health — true enough to be useless. Reviews of mitochondrial redox signalling in photobiomodulation describe plausible effects on oxidative signalling and inflammatory mediators, which is a reason to run trials in named conditions rather than a licence to make blanket claims.
Practical Guidance
Get a diagnosis before treating pain with anything. Keep light as an adjunct to loading, mobility work and professional rehabilitation. Expect modest, cumulative change rather than a dramatic response, and note that dose in PBM is biphasic — more is not better. Anyone with photosensitivity, on a photosensitizing medication, pregnant, or with an active malignancy should consult a physician before using any light device.
Related reading: red light therapy, cold plunge therapy, and the full Light System™ research guide.
Educational information only. Not medical advice, and not an offer of The Light System™ as a service at Sanctuary Tulum.