Magnesium Status and Its Association With Glycemic Control and Diabetes-Related Complications in Type 2 Diabetes Mellitus: A Systematic Review

Type 2 diabetes mellitus (T2DM) is frequently accompanied by disturbances in magnesium homeostasis, which may influence insulin action, glycemic regulation, and the development of vascular and neurological complications.Despite increasing interest in magnesium deficiency, evidence remains inconsistent because of variation in magnesium assessment, study design, clinical populations, and evaluated outcomes.This systematic review examined the relationship between magnesium status, glycemic control, diabetes-related complications, and the potential effects of magnesium supplementation primarily in adults with T2DM.PubMed/MEDLINE, Scopus, Google Scholar, and Web of Science were searched for original studies published between January 2020 and September 5, 2026.Of 252 identified records, 211 were screened after duplicate removal, 47 full-text articles were assessed, and 10 studies were included in the qualitative synthesis.Most included studies were cross-sectional or retrospective, with one randomized crossover trial.Lower magnesium status was commonly associated with poorer glycemic control, including elevated HbA1c and glucose concentrations, greater insulin resistance, and diabetes-related complications, such as retinopathy, neuropathy, nephropathy, and vascular disease.Magnesium exposure was assessed using serum magnesium, ionized and total magnesium, magnesium depletion scores, dietary magnesium intake, or supplementation.The randomized trial demonstrated an increase in serum magnesium concentrations without significant improvements in insulin sensitivity or glycemic outcomes.Current evidence suggests that magnesium status may be a relevant metabolic marker in T2DM; however, predominantly observational findings, methodological heterogeneity, and limited interventional evidence prevent causal conclusions or recommendations for routine magnesium supplementation.