title: Milk and dairy consumption and risk of bladder cancer: a meta-analysis.
abstract: OBJECTIVE
  To explore potential relations between the intake of milk or dairy products and the risk of bladder cancer.
  
  
  METHODS
  Eligible studies published up to May 2011 were retrieved via both computer searches and manual review of references. Random-effects models were used to calculate summary relative risk estimates (SRRE) based on high-contrast to low-intake values. Sensitivity and influence analyses were conducted, and heterogeneity among study results was explored through stratified analyses by study design, gender, geographic region, year of publication, or whether or not adjustment for several confounders (ie, age, gender, body mass index, smoking, and total energy intake).
  
  
  RESULTS
  We extracted data from 14 studies on milk (involving 4879 cases) and 6 studies on dairy products (3087 cases). The total study population was up to 324,241 individuals. Overall, there was no significant association between milk intake and bladder cancer (SRRE 0.89, 95% CI 0.77-1.02). However, an inverse association was found in the United States (SRRE 0.88, 95% CI .79-.99). In addition, no significant association was observed between consumption of dairy products and risk of bladder cancer (SRRE 0.95, 95% CI .71-1.27), though an inverse association was detected in the Japanese population (SRRE 0.56, 95% CI .40-.80).
  
  
  CONCLUSIONS
  There appears to be enough evidence to support the null hypothesis. The overall result was not statistically significant. The findings of this meta-analysis are not supportive of an independent relationship between the intake of milk or dairy products and the risk of bladder cancer. However, these findings are based on limited research. Further efforts should be made to confirm these findings.
authors.affiliation: Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Li
authors.forename: Sheng-li
authors.initials: SL
authors.lastname: An
authors.forename: You
authors.initials: Y
authors.lastname: Zhou
authors.forename: Zhong-kun
authors.initials: ZK
authors.lastname: Liang
authors.forename: Zhan-jiang
authors.initials: ZJ
authors.lastname: Jiao
authors.forename: Yu-ming
authors.initials: YM
authors.lastname: Jing
authors.forename: Pei
authors.initials: P
authors.lastname: Wan
authors.forename: Xiao-jun
authors.initials: XJ
authors.lastname: Shi
authors.forename: Wan-long
authors.initials: WL
authors.lastname: Tan
mesh_terms: D000818:Animals; D002417:Cattle; D003611:Dairy Products; D004032:Diet; D005260:Female; D006801:Humans; D008297:Male; D008892:Milk; D018570:Risk Assessment; D012307:Risk Factors; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology*