Clavel J1, Kisters K2, Vormann J3, Werner T1

1 Protina Pharmazeutische GmbH, 85737 Ismaning, Germany
2 St. Anna Hospital, 44649 Herne, Germany

3 Institute for Prevention and Nutrition, 85737 Ismaning, Germany

The present study evaluated the role of oral magnesium (Mg) supplementation in newly diagnosed, i.e. glycated hemoglobin (HbA1c) ≥5.7% and <6.5%, untreated prediabetic individuals without hypomagnesemia. 

Fifty subjects were randomly assigned to receive either 400 mg Mg in the form of Mg citrate or placebo daily for 12 weeks. All parameters were determined at baseline and after 12 weeks and complete dataset were obtained from n=19 in the Mg and n=18 in the placebo group.

In these normomagnesemic subjects, Mg supplementation led to a significant increase in plasma Mg concentration after 12 weeks (0.79 ± 0.08 mmol/L to 0.82 ± 0.07 mmol/L; p=0.02). HbA1c decreased significantly within the Mg group (6.23 ± 0.64% to 6.00 ± 0.55%; p<0.01) but showed no difference compared to placebo. Subjects in the Mg group showed a decrease in blood pressure (BP) after 12 weeks compared to baseline (baseline 144 ± 10 / 86 ± 4 mmHg; 12 weeks 122 ± 6 / 78 ± 3 mmHg; p <0.0001).

In untreated, normomagnesemic, prediabetic individuals, oral Mg citrate supplementation improved HbA1c and reduced high BP. Further interventional studies are required to determine the effect size of Mg supplementation on prediabetes and hypertension, especially to elucidate the optimal dosage and duration to prevent the progression from prediabetes to diabetes and thus provide optimal alternative strategies to medication.