Dietary magnesium intake and risk of metabolic syndrome: a meta-analysis

Abstract

Aims: To estimate quantitatively the association between dietary magnesium intake and risk of metabolic syndrome by combining the relevant published articles using meta-analysis.

Methods: We reviewed the relevant literature in PubMed and EMBASE published up until August 2013 and obtained additional information through Google or a hand search of the references in relevant articles. A random-effects or fixed-effects model, as appropriate, was used to pool the effect sizes on metabolic syndrome comparing individuals with the highest dietary magnesium intake with those having the lowest intake. The dose-response relationship was assessed for every 100-mg/day increment in magnesium intake and risk of metabolic syndrome.

Result: Six cross-sectional studies, including a total of 24 473 individuals and 6311 cases of metabolic syndrome, were identified as eligible for the meta-analysis. A weighted inverse association was found between dietary magnesium intake and the risk of metabolic syndrome (odds ratio 0.69, 95% CI 0.59, 0.81) comparing the highest with the lowest group. For every 100-mg/day increment in magnesium intake, the overall risk of having metabolic syndrome was lowered by 17% (odds ratio 0.83, 95% CI 0. 77, 0.89).

Conclusion: Findings from the present meta-analysis suggest that dietary magnesium intake is inversely associated with the prevalence of metabolic syndrome. Further studies, in particular well-designed longitudinal cohort studies and randomized placebo-controlled clinical trials, are warranted to provide solid evidence and to establish causal inference.

FIGURE 1

Study selection process. Mg, magnesium; MetS, metabolic syndrome; OR, odds ratio.

FIGURE 2

Multivariable adjusted odds ratios (95% CI) of having prevalent metabolic syndrome in participants with the highest level of dietary magnesium intake compared with those with the lowest. The overall estimate is from fixed-effects models. The dots indicate the adjusted odds ratios. The size of the shaded square is proportional to the weight of each study. Horizontal lines represent 95% CIs. The diamond markers indicate the pooled odds ratios. OR, odds ratio.

FIGURE 3

Multivariable adjusted odds ratios (95% CI) of having metabolic syndrome for every 100-mg/day dietary magnesium intake increment. The overall estimate is from a fixed-effects model. Dots indicate the adjusted odds ratios. The size of the shaded square is proportional to the weight of each study. Horizontal lines represent 95% CIs. Diamond markers indicate the pooled odds ratios. OR, odds ratio.