title: Dietary fat intake and endogenous sex steroid hormone levels in postmenopausal women.
abstract: OBJECTIVE
  To examine the relationship between plasma levels of reproductive sex steroid hormones in postmenopausal women and their reported fat intake.
  
  
  METHODS
  We measured plasma sex steroid hormones levels in plasma collected in 1989 and 1990 from 381 healthy postmenopausal women. For each woman, we measured fat intake in 1986 and 1990 by a food-frequency questionnaire. The cross-sectional associations between the percentage of energy from total and specific types of dietary fat intake and plasma hormone levels were assessed by linear regression, controlling for energy intake, obesity, and protein intake.
  
  
  RESULTS
  The plasma estradiol level was 4.3% lower (95% confidence limits, -8.3%, -0.2%) for a substitution of 5% of energy from fat intake for an equivalent amount of energy from carbohydrate when adjusted for obesity and other covariates. Estradiol was also inversely associated with all other fat types except trans fat; the inverse associations with vegetable fat and marine omega-3 fats were statistically significant.
  
  
  CONCLUSIONS
  We observed an inverse association between total fat intake averaged over 4 to 5 years and estradiol levels. This result is inconsistent with the hypothesis that fat intake predisposes to breast cancer risk by raising endogenous estrogen levels.
authors.affiliation: Channing Laboratory, Department of Medicine, and Division of Preventive Medicine, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Holmes
authors.forename: D
authors.initials: D
authors.lastname: Spiegelman
authors.forename: W C
authors.initials: WC
authors.lastname: Willett
authors.forename: J E
authors.initials: JE
authors.lastname: Manson
authors.forename: D J
authors.initials: DJ
authors.lastname: Hunter
authors.forename: R L
authors.initials: RL
authors.lastname: Barbieri
authors.forename: G A
authors.initials: GA
authors.lastname: Colditz
authors.forename: S E
authors.initials: SE
authors.lastname: Hankinson
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D004041:Dietary Fats / Q000009:adverse effects / Q000494:pharmacology*; D004043:Dietary Fiber / Q000494:pharmacology; D004044:Dietary Proteins / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D002149:Energy Intake; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D016014:Linear Models; D008875:Middle Aged; D015999:Multivariate Analysis; D017698:Postmenopause / Q000097:blood*; D013256:Steroids / Q000097:blood
chemical_list: D004041:Dietary Fats; D004043:Dietary Fiber; D004044:Dietary Proteins; D012739:Gonadal Steroid Hormones; D013256:Steroids