title: Intake of vitamins A, C, and E and folate and the risk of ovarian cancer in a pooled analysis of 10 cohort studies.
abstract: OBJECTIVE
  Vitamins A, C, and E and folate have anticarcinogenic properties and thus might protect against cancer. Few known modifiable risk factors for ovarian cancer exist. We examined the associations between dietary and total (food and supplemental) vitamin intake and the risk of invasive epithelial ovarian cancer.
  
  
  METHODS
  The primary data from 10 prospective cohort studies in North America and Europe were analyzed. Vitamin intakes were estimated from validated food frequency questionnaires in each study. Study-specific relative risks (RRs) were estimated using the Cox proportional hazards model and then combined using a random-effects model.
  
  
  RESULTS
  Among 501,857 women, 1,973 cases of ovarian cancer occurred over a median follow-up period of 7-16 years across studies. Dietary and total intakes of each vitamin were not significantly associated with ovarian cancer risk. The pooled multivariate RRs [95% confidence intervals (CIs)] for incremental increases in total intake of each vitamin were 1.02 (0.97-1.07) for vitamin A (increment: 1,300 mcg/day), 1.01 (0.99-1.04) for vitamin C (400 mg/day), 1.02 (0.97-1.06) for vitamin E (130 mg/day), and 1.01 (0.96-1.07) for folate (250 mcg/day). Multivitamin use (vs. nonuse) was not associated with ovarian cancer risk (pooled multivariate RR = 1.00, 95% CI 0.89-1.12). Associations did not vary substantially by study, or by subgroups of the population. Greater vitamin intakes were associated with modestly higher risks of endometrioid tumors (n = 156 cases), but not with other histological types.
  
  
  CONCLUSIONS
  These results suggest that consumption of vitamins A, C, and E and folate during adulthood does not play a major role in ovarian cancer risk.
authors.affiliation: CRCHUM (Centre de recherche du CHUM) and Department of Social and Preventive Medicine, Université de Montréal, 850 Saint-Denis Street, 2nd Floor, Montreal, QC, H2X 0A9, Canada, anita.koushik@umontreal.ca.
authors.forename: Anita
authors.initials: A
authors.lastname: Koushik
authors.forename: Molin
authors.initials: M
authors.lastname: Wang
authors.forename: Kristin E
authors.initials: KE
authors.lastname: Anderson
authors.forename: Piet
authors.initials: P
authors.lastname: van den Brandt
authors.forename: Tess V
authors.initials: TV
authors.lastname: Clendenen
authors.forename: A Heather
authors.initials: AH
authors.lastname: Eliassen
authors.forename: Jo L
authors.initials: JL
authors.lastname: Freudenheim
authors.forename: Jeanine M
authors.initials: JM
authors.lastname: Genkinger
authors.forename: Niclas
authors.initials: N
authors.lastname: Håkansson
authors.forename: James R
authors.initials: JR
authors.lastname: Marshall
authors.forename: Marjorie L
authors.initials: ML
authors.lastname: McCullough
authors.forename: Anthony B
authors.initials: AB
authors.lastname: Miller
authors.forename: Kim
authors.initials: K
authors.lastname: Robien
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Rohan
authors.forename: Catherine
authors.initials: C
authors.lastname: Schairer
authors.forename: Leo J
authors.initials: LJ
authors.lastname: Schouten
authors.forename: Shelley S
authors.initials: SS
authors.lastname: Tworoger
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Alicja
authors.initials: A
authors.lastname: Wolk
authors.forename: Anne
authors.initials: A
authors.lastname: Zeleniuch-Jacquotte
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Smith-Warner
mesh_terms: D000328:Adult; D001205:Ascorbic Acid / Q000009:adverse effects*; D000077216:Carcinoma, Ovarian Epithelial; D015331:Cohort Studies; D019587:Dietary Supplements / Q000009:adverse effects*; D005060:Europe / Q000453:epidemiology; D005260:Female; D005492:Folic Acid / Q000009:adverse effects*; D006801:Humans; D008875:Middle Aged; D009375:Neoplasms, Glandular and Epithelial / Q000453:epidemiology* / Q000209:etiology*; D009656:North America / Q000453:epidemiology; D010051:Ovarian Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D011446:Prospective Studies; D012306:Risk; D014801:Vitamin A / Q000009:adverse effects*; D014810:Vitamin E / Q000009:adverse effects*; D014815:Vitamins / Q000009:adverse effects*
chemical_list: D014815:Vitamins; D014801:Vitamin A; D014810:Vitamin E; D005492:Folic Acid; D001205:Ascorbic Acid