title: Dietary fiber intake and risk of type 2 diabetes: a dose-response analysis of prospective studies.
abstract: Observational studies suggest an association between dietary fiber intake and risk of type 2 diabetes, but the results are inconclusive. We conducted a meta-analysis of prospective studies evaluating the associations of dietary fiber intake and risk of type 2 diabetes. Relevant studies were identified by searching EMBASE (from 1974 to April 2013) and PubMed (from 1966 to April 2013). The fixed or random-effect model was selected based on the homogeneity test among studies. In addition, a 2-stage random-effects dose-response meta-analysis was performed. We identified 17 prospective cohort studies of dietary fiber intake and risk of type 2 diabetes involving 19,033 cases and 488,293 participants. The combined RR (95 % CI) of type 2 diabetes for intake of total dietary fiber, cereal fiber, fruit fiber and insoluble fiber was 0.81 (0.73-0.90), 0.77 (0.69-0.85), 0.94 (0.88-0.99) and 0.75 (0.63-0.89), respectively. A nonlinear relationship was found of total dietary fiber intake with risk of type 2 diabetes (P for nonlinearity < 0.01), and the RRs (95 % CI) of type 2 diabetes were 0.98 (0.90-1.06), 0.97 (0.87-1.07), 0.89 (0.80-0.99), 0.76 (0.65-0.88), and 0.66 (0.53-0.82) for 15, 20, 25, 30, and 35 g/day. The departure from nonlinear relationship was not significant (P for nonlinearity = 0.72), and the risk of type 2 diabetes decreased by 6 % (RR 0.94, 95 % CI 0.93-0.96) for 2 g/day increment in cereal fiber intake. Findings from this meta-analysis indicate that the intakes of dietary fiber may be inversely associated with risk of type 2 diabetes.
authors.affiliation: Shanghai Minhang Center for Disease Control and Prevention, 965 Zhongyi Road, Shanghai, 201101, China.
authors.forename: Baodong
authors.initials: B
authors.lastname: Yao
authors.forename: Hong
authors.initials: H
authors.lastname: Fang
authors.forename: Wanghong
authors.initials: W
authors.lastname: Xu
authors.forename: Yujie
authors.initials: Y
authors.lastname: Yan
authors.forename: Huilin
authors.initials: H
authors.lastname: Xu
authors.forename: Yinan
authors.initials: Y
authors.lastname: Liu
authors.forename: Miao
authors.initials: M
authors.lastname: Mo
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Yanping
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D003924:Diabetes Mellitus, Type 2 / Q000517:prevention & control*; D004032:Diet; D004043:Dietary Fiber / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D002523:Edible Grain; D005260:Female; D005638:Fruit; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D014675:Vegetables