Photobiomodulation Therapy to Improve Glycemic Control in People with Diabetes Mellitus: A Systematic Review

Objective: To evaluate the effects of photobiomodulation (PBM) on glycemic control in individuals with type 2 diabetes mellitus (T2DM). Persistent hyperglycemia in T2DM disrupts mitochondrial metabolism, increases oxidative stress, and contributes to metabolic and vascular complications. PBM has emerged as a potential nonpharmacological strategy to modulate mitochondrial function and improve metabolic homeostasis. Methods: Recent clinical trials investigating PBM in T2DM were systematically synthesized. Methodological quality was assessed using the Physiotherapy Evidence Database scale, and certainty of evidence was evaluated with the Grading of Recommendations, Assessment, Development, and Evaluation approach. Results: PBM, predominantly using red and near-infrared wavelengths, was associated with reductions in fasting glucose, postprandial glucose, and glycated hemoglobin, as well as modulation of hemodynamic and metabolic parameters. Methodological quality ranged from moderate to high, while certainty of evidence was very low to low. Conclusions: PBM shows potential as an adjunctive therapy for glycemic control in T2DM, although further well-designed trials are required to strengthen evidence and standardize protocols.