Effectiveness and Safety of Low-Level Red Light and Short-Wavelength Light Therapy for Myopia Control and Prevention in Children: A Systematic Review

Background: Myopia is a major public health challenge, particularly among children, with prevalence increasing worldwide. Emerging light-based interventions, including low-level red light (LLRL) and short-wavelength light therapy, may be effective for myopia control. This systematic review aimed to assess the effectiveness and safety of LLRL and short-wavelength light therapy for myopia control in children. Methods: A systematic search was performed in PubMed, Web of Science, Scopus, Google Scholar, and EBSCO in accordance with PRISMA 2020 guidelines. Studies published between 2013 and 2026 assessing the effectiveness and safety of LLRL and short-wavelength therapies for myopia control were included. The quality of the included studies was assessed using the Downs and Black checklist. Intervention outcomes included changes in axial length (AL), spherical equivalent refraction (SER), and choroidal thickness (CT). Safety outcomes comprised evaluations of both structural and functional retinal damage, along with assessment of ocular surface complications following the intervention. The review protocol was registered in PROSPERO (with registration number CRD420261289443). Results: Twenty-six studies reported that LLRL therapy effectively slowed myopia progression in children; however, some retinal structural and functional changes warrant further long-term safety evaluation. LLRL significantly reduced AL elongation and SER progression, increased macular CT, and delayed the onset of myopia. Some studies indicated that LLRL therapy may achieve greater efficacy in myopia control compared with 0.01% atropine. Reported adverse events include photophobia, dry eye symptoms, altered color perception, conjunctivitis, and visual discomfort. Six studies showed that short-wavelength light therapy reduced AL elongation and induced short-term choroidal changes. No serious ocular or systemic adverse events were reported with short-wavelength light therapy; however, long-term safety requires further investigation. Conclusions: Light-based therapies, particularly LLRL and short-wavelength light interventions, show promise as non-pharmacological approaches for myopia control; conversely, current evidence remains insufficient to establish their long-term safety. LLRL therapy has demonstrated efficacy in reducing AL, increasing CT, and delaying SER progression. However, reported retinal changes and ocular surface symptoms underscore the importance of close monitoring, standardized treatment protocols, and long-term safety evaluation in large-scale clinical trials.