MAGNESIUM supplementation has emerged as a potential adjunctive strategy for improving glycaemic control in people with Type 2 diabetes mellitus (T2D). With T2D continuing to pose a significant global health challenge, identifying low-risk, accessible interventions remains a key clinical priority. Magnesium, an essential mineral involved in insulin function and glucose metabolism, has attracted increasing attention in recent years. A recent study pooled data from randomised controlled trials to assess its impact. A key finding was that magnesium supplementation significantly reduced fasting blood glucose levels in people with T2D.
Researchers conducted a systematic review and meta-analysis of 23 randomised controlled trials involving a total of 1,345 participants diagnosed with T2D. The trials compared the effects of magnesium supplementation against placebo or standard care, assessing outcomes such as fasting blood glucose, glycated haemoglobin (HbA1c), serum magnesium levels, blood pressure and lipid profiles. Subgroup analyses were performed to explore the influence of age and supplementation duration.
The results demonstrated that magnesium supplementation significantly increased serum magnesium levels (weighted mean difference [WMD] = 0.69; 95% confidence interval [CI]: 0.32 to 1.06) and reduced fasting blood glucose (WMD = -0.58; 95% CI: -0.87 to -0.28). However, the overall effect on HbA1c was small and of borderline statistical significance (WMD = -0.16; 95% CI: -0.32 to 0.00). Subgroup analysis revealed more notable reductions in HbA1c among individuals aged 65 and older and in studies with longer intervention durations. Secondary findings included reductions in diastolic blood pressure and potential improvements in lipid profiles, suggesting broader cardiometabolic benefits.
While the findings indicate that magnesium supplementation may modestly improve fasting glucose levels in people with T2DM, its impact on long-term glycaemic control appears limited. The benefits observed in older adults and with prolonged use point to important considerations for clinical practice. Nonetheless, heterogeneity among studies, variations in dosage, and short intervention periods limit the generalisability of results. Further research is needed to determine optimal dosing strategies and identify patients most likely to benefit. Clinicians may wish to consider magnesium status as part of a holistic approach to managing type 2 diabetes, particularly in older patients or those with suboptimal glycaemic control.
Reference
Al Maqrashi N et al. Effect of Magnesium Supplements on Improving Glucose Control, Blood Pressure and Lipid Profile in Patients With Type 2 Diabetes Mellitus: A systematic review and meta-analysis. Sultan Qaboos Univ Med J. 2025;25(1):382-94.
