A total of 62 men and non-pregnant women aged 18-65 year , with new diagnosis of prediabetes ( glucose 5.6 < 7.0 mmol/L and/or post-load glucose 7.7 < 11.1 mmol/L ) and hypomagnesemia ( serum magnesium levels < 0.74 mmol/L ) were enrolled in a clinical double-blind placebo-controlled trial and randomly allocated to receive either magnesium chloride ( 30 mL of MgCl2 5 % solution ) or NaHCO3 0.1 % solution , once daily for 3 months .