title: Black tea consumption and risk of rectal cancer in Moscow population.
abstract: OBJECTIVE
  This population-based case-control study (663 cases and 323 controls) examined the effect of black tea intake on the risk of rectal cancer in Moscow residents. The Moscow population was selected for its wide range of black tea consumption.
  
  
  METHODS
  This study used three measures of tea consumption: the volume of beverage (l/month), zavarka (tea concentrate, l/month), and dry tea (g/month). We calculated the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for these three parameters of tea intake using logistic regression.
  
  
  RESULTS
  Greater use of dry tea was associated with lower risk of rectal cancer in women (high vs. low: OR = 0.40; 95% CI, 0.23-0.70) and in men (high vs. low: OR = 0.77; 95% CI, 0.42-1.43). The observed effect was weaker when tea was measured as zavarka (high vs. low in women: OR = 0.47; 95% CI, 0.26-0.83; in men: OR = 0.99; 95% CI, 0.52-1.96) and as beverage volume (high vs. low in women: OR = 0.68; 95% CI, 0.39-1.19; in men: OR = 1.03; 95% CI, 0.53-2.09).
  
  
  CONCLUSIONS
  These findings support the hypothesis that black tea consumption reduces the risk of rectal cancer. The attenuation of the effect across the three measures of tea intake can be explained by an increasing degree of exposure misclassification from dry tea to zavarka and beverage volume.
authors.affiliation: Department of Epidemiology, University of North Carolina at, Chapel Hill, NC 27157, USA. dilyasov@wfubmc.edu
authors.forename: Il'yasova
authors.initials: I
authors.lastname: Dora
authors.forename: Lenore
authors.initials: L
authors.lastname: Arab
authors.forename: Arseny
authors.initials: A
authors.lastname: Martinchik
authors.forename: Alexander
authors.initials: A
authors.lastname: Sdvizhkov
authors.forename: Leonard
authors.initials: L
authors.lastname: Urbanovich
authors.forename: Ute
authors.initials: U
authors.lastname: Weisgerber
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology / Q000517:prevention & control; D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000009:adverse effects; D028241:Camellia sinensis; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000517:prevention & control; D015986:Confounding Factors, Epidemiologic; D004305:Dose-Response Relationship, Drug; D004327:Drinking Behavior; D005260:Female; D006306:Health Surveys; D006801:Humans; D007407:Interviews as Topic; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009031:Moscow / Q000453:epidemiology; D012042:Registries; D012307:Risk Factors; D012737:Sex Factors; D013662:Tea
chemical_list: D013662:Tea