Association between magnesium and vitamin D status in adults with high prevalence of vitamin D deficiency and insufficiency

Purpose: It has been assumed that magnesium (Mg) status may interact with vitamin D status. We therefore aimed at investigating the association between Mg and vitamin D status in a large cohort of adult individuals with a high prevalence of deficient/insufficient vitamin D and Mg status.

Methods: We used data from the Ludwigshafen Risk and Cardiovascular Health Study (n = 2,286) to analyze differences according to serum Mg status in circulating 25-hydroxyvitamin D [25(OH)D] (primary endpoint), 24,25-dihydroxyvitamin D₃ [24,25(OH)₂D₃], vitamin D metabolite ratio and calcitriol, and odds ratios for deficient or insufficient 25(OH)D (secondary endpoints). We performed unadjusted and risk score (RS) adjusted and matched analyses.

Results: Of the study cohort (average age > 60 years), one third was 25(OH)D deficient (< 12 ng/mL), one third 25(OH)D insufficient (12 to < 20 ng/mL), about 10% Mg deficient (< 0.75 mmol/L) and additional 40% potentially Mg deficient (0.75 to 0.85 mmol/L). In adjusted/matched analyses, 25(OH)D was only non-significantly lower in Mg deficient or insufficient groups versus their respective control group (P > 0.05). Only the RS-adjusted, but not the RS-matched odds ratio of 25(OH)D deficiency was significantly lower for the group with adequate versus deficient/potentially deficient Mg status (0.83; 95%CI: 0.69-0.99), and only the RS-matched, but not the RS-adjusted odds ratio of 25(OH)D insufficiency was significantly lower for non-deficient versus deficient Mg status (0.69; 95%CI: 0.48-0.99). Other adjusted or matched secondary endpoints did not differ significantly between subgroups of Mg status.

Conclusions: Our data indicate only little effect between Mg and vitamin D status in adults with high prevalence of vitamin D deficiency and insufficiency.