title: Dietary vitamin A intake and incidence of gastric cancer in a general Japanese population: the Hisayama Study.
abstract: BACKGROUND
  The results of prospective studies examining the association between dietary vitamin A intake and the risk of gastric cancer have often been conflicting. The objective of this study was to investigate this issue in a general Japanese population.
  
  
  METHODS
  A total of 2,467 community-dwelling Japanese subjects aged 40 years or older were followed up prospectively for 14 years. Dietary vitamin A intake was estimated using a semiquantitative food frequency method.
  
  
  RESULTS
  During the follow-up period, gastric cancer developed in 93 subjects. The age- and sex-adjusted incidence of gastric cancer rose progressively with increasing levels of dietary vitamin A intake: at 2.2, 3.0, 3.8, and 4.5 per 1,000 person-years for quartile groups defined by dietary vitamin A intake levels of <639, 639-837, 838-1,061, and >1,061 μg retinol equivalents (RE)/day, respectively (P for trend <0.01). The risk of gastric cancer was significantly higher in the fourth quartile than in the first one even after multivariate adjustment [hazard ratio (HR) = 1.47, 95% confidence interval (CI) = 0.70-3.09, P = 0.30 for the second quartile; HR = 1.85, 95% CI = 0.82-4.18, P = 0.14 for the third quartile; HR = 2.96, 95% CI = 1.12-7.80, P = 0.03 for the fourth quartile]. Comparable effects of vitamin A intake were observed irrespective of the location or histological type of gastric cancer. The HR for gastric cancer increased significantly only in subjects with a combination of high vitamin A intake (>1,061 μg RE/day) and Helicobacter pylori infection.
  
  
  CONCLUSIONS
  Our findings suggest that dietary vitamin A intake is clearly associated with the risk of gastric cancer in the general Japanese population.
authors.affiliation: Department of Environmental Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Miyazaki
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Doi
authors.forename: Fumie
authors.initials: F
authors.lastname: Ikeda
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Ninomiya
authors.forename: Jun
authors.initials: J
authors.lastname: Hata
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Uchida
authors.forename: Tomoko
authors.initials: T
authors.lastname: Shirota
authors.forename: Takayuki
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Iida
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kiyohara
mesh_terms: D004032:Diet; D005260:Female; D005500:Follow-Up Studies; D016481:Helicobacter Infections / Q000150:complications*; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D016016:Proportional Hazards Models; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000209:etiology; D014801:Vitamin A / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D014801:Vitamin A