Effects of photobiomodulation on glucose metabolism and perspective of its practical applications: a systematic review

Introduction: Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycemia due to insulin deficiency and/or resistance, leading to classic symptoms, as well as microvascular and macrovascular complications that affect patients’ quality of life. Evidence demonstrates that strict glycemic control can mitigate the risk and severity of these complications. In this context, photobiomodulation (PBM) has emerged as a potential alternative for optimizing glycemic control. PBM uses light in the red/near-infrared range, which can penetrate tissues and trigger biological responses. This systematic review aimed to investigate the effects of PBM on the reduction of plasma glucose levels and its applicability in managing metabolic control of DM and its associated complications. Methods: This systematic review was conducted using the PubMed, Scopus and Clinical Trials.gov databases and the last search was conducted on the 26th of April 2025. Methodological quality and risk of bias were assessed using the Cochrane RoB2 tool and GRADE to ensure evidence reliability, following PRISMA guidelines. Results: PBM improved the healing of diabetic ulcers and reduced neuropathic pain. However, methodological quality varied within the studies with varying risks of bias due to the variety of PBM protocols and the heterogeneity of the results, limiting the comparison. Conclusion: PBM demonstrates considerable therapeutic potential for the management of complications associated with DM, while in terms of glycemic control the results were, for now, discouraging. However, further studies involving larger sample sizes and more standardized protocols are required to validate its efficacy and to determine the best therapeutic conditions.