title: Dietary phytoestrogen, serum enterolactone and risk of prostate cancer: the cancer prostate Sweden study (Sweden).
abstract: OBJECTIVE
  Based on evidence that phytoestrogens may protect against prostate cancer, we evaluated the associations between serum enterolactone concentration or dietary phytoestrogen intake and risk of prostate cancer.
  
  
  METHODS
  In our Swedish population-based case-control study, questionnaire-data were available for 1,499 prostate cancer cases and 1,130 controls, with serum enterolactone levels in a sub-group of 209 cases and 214 controls. Unconditional logistic regression was performed to estimate multivariate odds ratios (ORs) and 95% confidence intervals (CIs) for associations with risk of prostate cancer.
  
  
  RESULTS
  High intake of food items rich in phytoestrogens was associated with a decreased risk of prostate cancer. The OR comparing the highest to the lowest quartile of intake was 0.74 (95% CI: 0.57-0.95; p-value for trend: 0.01). In contrast, we found no association between dietary intake of total or individual lignans or isoflavonoids and risk of prostate cancer. Intermediate serum levels of enterolactone were associated with a decreased risk of prostate cancer. The ORs comparing increasing quartiles of serum enterolactone concentration to the lowest quartile were, respectively, 0.28 (95% CI: 0.15-0.55), 0.63 (95% CI: 0.35-1.14) and 0.74 (95% CI: 0.41-1.32).
  
  
  CONCLUSIONS
  Our results support the hypothesis that certain foods high in phytoestrogens are associated with a lower risk of prostate cancer.
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Box 281, SE-171 77, Stockholm, Sweden. maria.hedelin@ki.se
authors.forename: Maria
authors.initials: M
authors.lastname: Hedelin
authors.forename: Asa
authors.initials: A
authors.lastname: Klint
authors.forename: Ellen T
authors.initials: ET
authors.lastname: Chang
authors.forename: Rino
authors.initials: R
authors.lastname: Bellocco
authors.forename: Jan-Erik
authors.initials: JE
authors.lastname: Johansson
authors.forename: Swen-Olof
authors.initials: SO
authors.lastname: Andersson
authors.forename: Satu-Maarit
authors.initials: SM
authors.lastname: Heinonen
authors.forename: Herman
authors.initials: H
authors.lastname: Adlercreutz
authors.forename: Hans-Olov
authors.initials: HO
authors.lastname: Adami
authors.forename: Henrik
authors.initials: H
authors.lastname: Grönberg
authors.forename: Katarina Augustsson
authors.initials: KA
authors.lastname: Bälter
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use; D004032:Diet; D015438:Health Behavior; D006801:Humans; D008019:Life Style; D017705:Lignans / Q000097:blood* / Q000627:therapeutic use; D008297:Male; D048789:Phytoestrogens / Q000627:therapeutic use*; D011471:Prostatic Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control*; D012307:Risk Factors; D013548:Sweden
chemical_list: D017705:Lignans; D048789:Phytoestrogens; D015107:4-Butyrolactone; C029497:2,3-bis(3'-hydroxybenzyl)butyrolactone