title: Association between vitamin A, retinol intake and blood retinol level and gastric cancer risk: A meta-analysis.
abstract: OBJECTIVE
  The association between dietary vitamin A, retinol intake and blood retinol level and gastric cancer risk has been investigated by many studies. However, the results of these studies were controversial. The aim of our study was to systematically assess this issue.
  
  
  METHODS
  PUBMED and EMBASE were searched, supplemented with manual-screening for relevant publications. Meta-analyses were performed to evaluate the association between vitamin A, retinol dietary intake or blood retinol level and gastric cancer risk.
  
  
  RESULTS
  Thirty-one studies were included in this meta-analysis. Comparing the highest with the lowest categories, vitamin A intake significantly reduced gastric cancer risk (pooled RR = 0.66, 95% CI: 0.52-0.84), whereas a marginally inverse association was found between retinol intake (pooled RR = 0.94, 95% CI: 0.87-1.03) or blood retinol level (pooled RR = 0.87, 95% CI: 0.73-1.05) and gastric cancer risk. Interestingly, the results of subgroup analysis indicated that high vitamin A intake and blood retinol level were associated with reduced gastric cancer risk in Western countries, while a marginally inverse association was found between retinol and gastric cancer risk in Western countries.
  
  
  CONCLUSIONS
  Vitamin A intake was inversely associated with gastric cancer risk, while no significant association was found with retinol intake or blood retinol level.
authors.affiliation: Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Epidemiology and Health Statistics, Zhejiang University School of Public Health, Hangzhou 310058, China.
authors.forename: Yihua
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Epidemiology and Health Statistics, Zhejiang University School of Public Health, Hangzhou 310058, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Ye
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Epidemiology and Health Statistics, Zhejiang University School of Public Health, Hangzhou 310058, China.
authors.forename: Peiwei
authors.initials: P
authors.lastname: Li
authors.affiliation: Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Epidemiology and Health Statistics, Zhejiang University School of Public Health, Hangzhou 310058, China.
authors.forename: Jinming
authors.initials: J
authors.lastname: Xu
authors.affiliation: Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Epidemiology and Health Statistics, Zhejiang University School of Public Health, Hangzhou 310058, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Chen
authors.affiliation: Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Pathology, Zhejiang University School of Medicine, Hangzhou 310058, China. Electronic address: xep@zju.edu.cn.
authors.forename: Enping
authors.initials: E
authors.lastname: Xu
authors.affiliation: Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital of Zhejiang University, Hangzhou 310003, China; Department of Medicine, Hangzhou Normal University, 16, Xuelin Str., Xiasha High Education Zone, Hangzhou, Zhejiang 310036, China. Electronic address: gastate@yahoo.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
mesh_terms: D016208:Databases, Factual; D006801:Humans; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000517:prevention & control*; D014801:Vitamin A / Q000008:administration & dosage* / Q000097:blood*
chemical_list: D014801:Vitamin A
keywords: Gastric cancer; Incidence; Meta-analysis; Retinol; Vitamin A