title: Dietary fiber intake and risk of renal cell carcinoma: evidence from a meta-analysis.
abstract: The aim of this study was to investigate the possible relationships between dietary fiber intake and risk of renal cell carcinoma (RCC). Electronic databases including MEDLINE, EMBASE and Web of Science were searched to find eligible studies. Random-effects relative risk (RR) and its corresponding 95 % confidence interval (CI) were used. Besides, random-effects dose-response analyses were also performed to clarify the dose-response relations. Finally, publication bias was assessed by Egger's test and Begg's test. All p values were two tailed. Seven studies, including two cohort studies and five case-control studies, were eligible and included in this meta-analysis. Overall analysis in highest versus lowest level revealed that total dietary fiber intake was associated with reduced RCC risk (RR 0.84, 95 % CI 0.74-0.96). In addition, pooled estimated data showed that risk of RCC was significantly associated with vegetable and legume fiber intake (RR 0.70, RR 0.80, respectively), but not with fruit and cereal fiber intake (RR 0.92, RR 1.04, respectively). However, in dose-response analysis, no significant association was reported. Finally, no publication bias was detected by Egger's or Begg's test. The dietary fiber intake, especially vegetable and legume fiber, may be associated with reduced RCC risk. Considering the limitations of the included studies, more well-designed prospective studies will be needed to confirm our findings.
authors.affiliation: Department of Urology, Shanghai Tenth People's Hospital, Tongji University, 301 Yanchang Road, Shanghai, 200072, China.
authors.forename: Tian-bao
authors.initials: TB
authors.lastname: Huang
authors.forename: Pei-pei
authors.initials: PP
authors.lastname: Ding
authors.forename: Jian-feng
authors.initials: JF
authors.lastname: Chen
authors.forename: Yang
authors.initials: Y
authors.lastname: Yan
authors.forename: Long
authors.initials: L
authors.lastname: Zhang
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
authors.forename: Peng-cheng
authors.initials: PC
authors.lastname: Liu
authors.forename: Jian-ping
authors.initials: JP
authors.lastname: Che
authors.forename: Jun-hua
authors.initials: JH
authors.lastname: Zheng
authors.forename: Xu-dong
authors.initials: XD
authors.lastname: Yao
mesh_terms: D002292:Carcinoma, Renal Cell / Q000209:etiology*; D016022:Case-Control Studies; D004043:Dietary Fiber / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D002523:Edible Grain; D007887:Fabaceae; D005638:Fruit; D006801:Humans; D007680:Kidney Neoplasms / Q000209:etiology*; D012307:Risk Factors; D014675:Vegetables