Chinese researchers set out to investigate this further, and their results were published in the September 2011 issue of Diabetes Care in an article called “Magnesium intake and risk of type 2 diabetes: meta-analysis of prospective cohort studies.”
They conducted a PubMed database search through January 2011 to identify prospective cohort studies of magnesium intake and type 2 diabetes risk. The references for the articles used in the study were also reviewed, and a random-effects model to calculate summary risk estimates was used as well.
This meta-analysis of 13 prospective cohort studies, which included 536,318 participants and 24,516 cases, detected a significant inverse association between magnesium intake and type 2 diabetes risk (relative risk [RR] 0.78 [95% CI; 0.73 to 0.84]); and this was not significantly modified by geographic region, follow-up length, sex, or family history of type 2 diabetes.
Furthermore, researchers observed a significant inverse association in overweight patients (body mass index [BMI] ≥25) but not in patients of normal weight (BMI <25). However, test for interaction was not statistically significant (p interaction=0.13); and the summary RR of type 2 diabetes for every 100 mg/day increment in magnesium intake was 0.86 (95% CI; 0.82 to 0.89) in the dose-response analysis.
In addition, researchers noted that sensitivity analyses restricted to studies with adjustment for cereal fiber intake yielded comparable results. Little evidence of publication bias was seen.
They concluded that this meta-analysis provides further confirmation that magnesium intake is considerably inversely associated with the risk of type 2 diabetes in a dose-response manner.