This week’s newest studies in red light therapy and photobiomodulation. See last week’s research here.
This Week in Red Light Therapy
This was a strong week for clinical results, covering childhood eye health, blood sugar management, and pain relief – plus one case report that device users should know about.
- Myopia in kids: Red light therapy beat prescription eye drops at preventing nearsightedness over 12 months, cutting the risk by 60%.
- Blood sugar: Vascular red light therapy produced dramatic same-session blood glucose drops in type 2 diabetic patients on metformin.
- Muscle and joint pain: A pilot study found 92% of participants with chronic pain reported improvement after 10 full-body red light sessions.
- Device safety: A rare case report linked two weeks of at-home red light mask use to a serious eye condition.
- Joint repair (animal study): Combining red light therapy with PRP injections preserved knee cartilage better than either treatment alone in rats.
Red Light Therapy Outperformed Eye Drops at Preventing Childhood Myopia
The study: Researchers in China followed 216 children aged 7-12 for 12 months, comparing daily repeated low-level red light (RLRL) therapy to 0.01% low-dose atropine eye drops, the current standard for slowing or preventing myopia.
What they found:
- Myopia incidence was 13.3% in the red light group versus 30.7% in the eye drop group – a 60% relative risk reduction with red light therapy.
- Children using red light therapy had a stable refractive error (0.08 diopter change) compared to a significant shift in the eye drop group (-0.49 diopters).
- Eye length growth averaged 0.02 mm in the red light group versus 0.29 mm in the atropine group – a meaningful difference, since elongation is what drives worsening myopia.
- Nearly 20% of kids on atropine reported photophobia (light sensitivity). No adverse events occurred in the red light group.
What this means for you: If you have children who are myopic or at risk, this 12-month study adds to a growing body of evidence that red light therapy for eye health may be a safer and more effective option than low-dose atropine – though this was a prospective comparison study, not a randomized trial.
Red Light Therapy Cut Blood Sugar Levels in Patients With Type 2 Diabetes
The study: A prospective single-arm clinical study tested vascular photobiomodulation (VPBM) – red light delivered over blood vessels rather than directly to tissue – in patients with type 2 diabetes who were already taking metformin.
What they found:
- Blood glucose dropped significantly in the same session, every time – from averages of 180-220 mg/dL before treatment down to 119-129 mg/dL immediately after.
- Baseline fasting glucose decreased meaningfully over the 6-week protocol.
- HbA1c (the longer-term blood sugar marker) didn’t change significantly, which isn’t surprising for a 6-week timeframe.
What this means for you: This is a preliminary study with no control group, so these results can’t be taken as proof of efficacy on their own. But the consistency of the same-session glucose drops across all sessions is hard to ignore. Larger controlled trials are needed before anyone managing diabetes should change their treatment plan based on this.
Full-Body Red Light Therapy Relieved Muscle and Joint Pain in 9 Out of 10 People
The study: Researchers enrolled 40 adults with acute or chronic musculoskeletal pain in a 10-session full-body LED protocol using red and near-infrared wavelengths (630, 660, 830, and 850 nm), 20 minutes per session. The group was predominantly Hispanic and Latino, a population underrepresented in photobiomodulation research.
What they found:
- 92.1% of participants reported global improvement after completing the protocol.
- 74.3% felt immediate pain relief after the very first session.
- Estimated total pain burden dropped from a median score of 6.0 to 3.5.
- Functional improvements ranged from 60% (sleep quality) to 82.5% (muscle stiffness and energy).
- One participant reported mild discomfort; no other adverse events were recorded.
What this means for you: There was no control group here, so some of this improvement may reflect the placebo effect or natural recovery. That said, the results are consistent with what red light therapy for athletes and recovery research has been showing, and a 74% immediate response rate after one session is notable. A sham-controlled follow-up is needed to know how much of this holds up.
A Red Light Therapy Mask Triggered a Rare Eye Condition in One User
The study: A case report from ophthalmologists describes a 43-year-old woman with no prior eye problems who developed acute bilateral angle-closure glaucoma (a sudden, serious spike in eye pressure) after two weeks of daily at-home red light therapy mask use. The most likely mechanism was ciliochoroidal effusions – fluid buildup behind the eye driven by increased blood vessel activity from the light exposure. She was treated, stopped using the mask, and fully recovered to 20/20 vision.
What this means for you: This is one case – not evidence that red light masks routinely cause glaucoma. But the authors note that red light is known to increase choroidal vascularity, and people with certain anatomical eye features may be more susceptible. If you’re using a red light therapy device near your eyes and experience eye pain, blurred vision, or halos around lights, stop using it and see an eye doctor.
This was a single case report – an early signal worth watching, not established cause and effect.
Combining Red Light Therapy With PRP May Protect Knee Joints Better Than Either Alone
The study: Brazilian researchers induced knee osteoarthritis in 18 rats and divided them into three groups: photobiomodulation (PBM) alone, platelet-rich plasma (PRP) injections alone, or both combined. They then examined cartilage structure and inflammation markers.
What they found:
- The combined PBM + PRP group showed the best cartilage preservation – tissue that looked closest to healthy cartilage under examination.
- Red light therapy alone effectively reduced joint inflammation.
- PRP alone improved outcomes but not to the same degree as the combination.
What this means for you: Many people already using red light therapy for arthritis or recovering from joint injuries also receive PRP injections. This animal study suggests the two may work better together than separately, likely because PBM supports the cellular environment while PRP delivers the growth factors. Human trials are the necessary next step.
This was an animal study – an early step in research. Results may not translate directly to humans.
Sources
- Ma et al. “Comparison of effects between daily repeated low-level red light therapy and 0.01% low-dose atropine for myopia prevention: A propensity score matching study.” Photodiagnosis and Photodynamic Therapy, 2026. PubMed
- Almeida et al. “Effects of Vascular Photobiomodulation on Glycemic Control in Patients With Type II Diabetes Mellitus: A Prospective Single-Arm Clinical Study.” Lasers in Surgery and Medicine, 2026. PubMed
- Scoz et al. “Feasibility and Patient-Reported Outcomes of Full-Body Red and Near-Infrared Photobiomodulation for Musculoskeletal Pain in a Predominantly Hispanic/Latino Population: A Single-Arm Pilot Study.” Photobiomodulation, Photomedicine, and Laser Surgery, 2026. PubMed
- Labkovich. “A rare acute presentation of simultaneous bilateral angle closure in a patient using a red light therapy mask.” American Journal of Ophthalmology Case Reports, 2026. PubMed
- Missrie et al. “Comparative Effects of Photobiomodulation and Platelet-Rich Plasma on Joint Repair in Rats With Knee Osteoarthritis.” Lasers in Surgery and Medicine, 2026. PubMed
