Dietary calcium intake and risk of type 2 diabetes: possible confounding by magnesium.
This study examined the association of dietary calcium intake with incident type 2 diabetes by a meta-analysis and explored the potential confounding by magnesium. Potential studies were identified by searching the PubMed database in September 2011. Prospective cohort studies that reported relative risks (RR) with 95% confidence intervals (CI) of type 2 diabetes for dietary calcium intake were selected. Results were combined using either a fixed- or random-effects model. Six prospective cohort studies comprising 264268 participants and 11225 reported cases were included. All combined random-effects meta-analysis yielded a significant pooled RR of 0.85 (95% CI 0.75-0.97). However, a sensitivity analysis limited to four studies with control for magnesium yielded an attenuated, nonsignificant pooled RR of 0.94 (95% CI 0.85-1.05). In conclusion, dietary calcium intake was not independently associated with risk of type 2 diabetes. The inverse association in prior observational studies may be partially confounded by magnesium intake.
Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, Suzhou, China.
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Dong
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Qin
D002118:Calcium / Q000008:administration & dosage / Q000172:deficiency / Q000494:pharmacology*; D002136:Calcium, Dietary / Q000008:administration & dosage / Q000494:pharmacology*; D015986:Confounding Factors, Epidemiologic; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D008274:Magnesium / Q000008:administration & dosage / Q000494:pharmacology*; D008275:Magnesium Deficiency / Q000150:complications*; D012307:Risk Factors
D002136:Calcium, Dietary; D008274:Magnesium; D002118:Calcium