Magnesium intake in relation to systemic inflammation, insulin resistance, and the incidence of diabetes

Abstract

Objective: To investigate the long-term associations of magnesium intake with incidence of diabetes, systemic inflammation, and insulin resistance among young American adults.

Research design and methods: A total of 4,497 Americans, aged 18-30 years, who had no diabetes at baseline, were prospectively examined for incident diabetes based on quintiles of magnesium intake. We also investigated the associations between magnesium intake and inflammatory markers, i.e., high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and fibrinogen, and the homeostasis model assessment of insulin resistance (HOMA-IR).

Results: During the 20-year follow-up, 330 incident cases of diabetes were identified. Magnesium intake was inversely associated with incidence of diabetes after adjustment for potential confounders. The multivariable-adjusted hazard ratio of diabetes for participants in the highest quintile of magnesium intake was 0.53 (95% CI, 0.32-0.86; P(trend) < 0.01) compared with those in the lowest quintile. Consistently, magnesium intake was significantly inversely associated with hs-CRP, IL-6, fibrinogen, and HOMA-IR, and serum magnesium levels were inversely correlated with hs-CRP and HOMA-IR.

Conclusions: Magnesium intake was inversely longitudinally associated with incidence of diabetes in young American adults. This inverse association may be explained, at least in part, by the inverse correlations of magnesium intake with systemic inflammation and insulin resistance.

Figure 1

HRs (95% CI) for incident diabetes in participants in the highest magnesium intake quintile compared with those in the lowest quintile, stratified by sex, ethnicity, family history of diabetes, and BMI. Data in the parentheses in the group column are the ratio of the number of events to number of participants. The adjusted covariates in the models were the same as those for model 3 in Table 2. *Continuous variables using the median value in each quintile were created for trend tests. A.A., African American; FH, family history.