title: Association between habitual dietary flavonoid and lignan intake and colorectal cancer in a Spanish case-control study (the Bellvitge Colorectal Cancer Study).
abstract: BACKGROUND
  Flavonoid-rich foods, such as fruits, vegetables, and tea, may have a protective effect upon colorectal cancer. However, current epidemiological evidence for a protective effect of flavonoid intake upon colorectal cancer is promising but not conclusive.
  
  
  OBJECTIVE
  To examine the relation between dietary flavonoid and lignan intakes and the risk of colorectal cancer within a Spanish population.
  
  
  METHODS
  Data from the Bellvitge Colorectal Cancer Study, a case-control study (424 cases with incident colorectal cancer and 401 hospital-based controls), were used. A reproducible and validated food frequency questionnaire was administered in personal interviews. An ad hoc food composition database on flavonoids and lignans was compiled, mainly using data from the US Department of Agriculture and Phenol-Explorer databases. Adjusted odds ratios (ORs) and 95 % confidence intervals (CIs) were estimated using unconditional logistic regression models.
  
  
  RESULTS
  An inverse association was found between intake of total flavonoids (OR, 0.59; 95 % CI, 0.35-0.99 for the highest vs. the lowest quartile; p for trend = 0.04), lignans (OR, 0.59; 95 % CI, 0.34-0.99; p for trend = 0.03), and some individual flavonoid subgroups (flavones, proanthocyanidins) and the risk of colorectal cancer. Separate analyses by cancer site showed similar results.
  
  
  CONCLUSIONS
  Intake of total dietary flavonoids (particularly certain flavonoid subgroups) and lignans was inversely associated with colorectal cancer risk in a Spanish population.
authors.affiliation: Unit of Nutrition, Environment and Cancer, Cancer Epidemiology Research Programme, Catalan Institute of Oncology, Avda Gran Via 199-203, 08907 L'Hospitalet de Llobregat, Barcelona, Spain. rzamora@iconcologia.net
authors.forename: Raul
authors.initials: R
authors.lastname: Zamora-Ros
authors.forename: Carla
authors.initials: C
authors.lastname: Not
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Guinó
authors.forename: Leila
authors.initials: L
authors.lastname: Luján-Barroso
authors.forename: Raul M
authors.initials: RM
authors.lastname: García
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Biondo
authors.forename: Ramón
authors.initials: R
authors.lastname: Salazar
authors.forename: Victor
authors.initials: V
authors.lastname: Moreno
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D004032:Diet / Q000706:statistics & numerical data*; D005260:Female; D005419:Flavonoids / Q000008:administration & dosage*; D005638:Fruit; D006801:Humans; D015994:Incidence; D017705:Lignans / Q000008:administration & dosage*; D008297:Male; D013030:Spain / Q000453:epidemiology; D014675:Vegetables
chemical_list: D005419:Flavonoids; D017705:Lignans