title: Association between vitamin C intake and glioma risk: evidence from a meta-analysis.
abstract: BACKGROUND
  The field of quantifying the association between the intake of vitamin C and risk of glioma still has conflicts. Thus, we performed a comprehensive meta-analysis to test the hypothesis that a high intake of vitamin C may be a protective effect on glioma risk.
  
  
  METHODS
  Pertinent studies were identified by a search in PubMed and Web of Knowledge up to June 2014. The random-effect model was used to combine study-specific results. Publication bias was estimated using Begg' funnel plot and Egger's regression asymmetry test.
  
  
  RESULTS
  Thirteen articles with 15 studies (2 cohort study and 13 case-control studies) involving 3,409 glioma cases about vitamin C intake and glioma risk were used in this meta-analysis. The combined relative risks (RRs) of glioma associated with vitamin C intake was 0.86 (95% CIs = 0.75-0.99). Overall, significant protective associations were also found in the American population (RRs = 0.85, 95% CIs = 0.73-0.98) and case-control studies (RRs = 0.80, 95% CIs = 0.69-0.93). No publication bias was found.
  
  
  CONCLUSIONS
  Our analysis indicated that vitamin C intake might decrease the risk of glioma, especially among the Americans.
authors.forename: Siru
authors.initials: S
authors.lastname: Zhou
authors.forename: Xiaoya
authors.initials: X
authors.lastname: Wang
authors.forename: Ya
authors.initials: Y
authors.lastname: Tan
authors.forename: Lingli
authors.initials: L
authors.lastname: Qiu
authors.forename: Huan
authors.initials: H
authors.lastname: Fang
authors.forename: Wei
authors.initials: W
authors.lastname: Li
mesh_terms: D001205:Ascorbic Acid / Q000008:administration & dosage*; D001932:Brain Neoplasms / Q000453:epidemiology* / Q000517:prevention & control; D004032:Diet; D005910:Glioma / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D012306:Risk
chemical_list: D001205:Ascorbic Acid