title: Diet and sex hormones in girls: findings from a randomized controlled clinical trial.
abstract: BACKGROUND
  Results of several studies have suggested that diet during adolescence may influence the risk of breast cancer in adulthood. We evaluated whether an intervention to lower fat intake among adolescent girls altered their serum concentrations of sex hormones that, in adults, are related to breast cancer development.
  
  
  METHODS
  We conducted an ancillary hormone study among 286 of the 301 girls who participated between 1988 and 1997 in the Dietary Intervention Study in Children, in which healthy, prepubertal, 8- to 10-year-olds with elevated low-density lipoprotein cholesterol were randomly assigned to usual care or to a behavioral intervention that promoted a low-fat diet. Median time on the intervention was 7 years. Blood samples collected before randomization and at the year 1, year 3, year 5, and last visits were assayed to determine the girls' serum levels of sex hormones. All P values are two-sided.
  
  
  RESULTS
  At the year 5 visit, girls in the intervention group had 29.8% (95% confidence interval [CI] = 5.4% to 47.9%; P =.02) lower estradiol, 30.2% (95% CI = 7.0% to 47.7%; P =.02) lower non-sex hormone binding globulin-bound estradiol, 20.7% (95% CI = 4.7% to 34.0%; P =.02) lower estrone, and 28.7% (95% CI = 5.1% to 46.5%; P =.02) lower estrone sulfate levels during the follicular phase of the menstrual cycle and 27.2% (95% CI = 5.7% to 53.1%; P =.01) higher testosterone levels during the luteal phase of the menstrual cycle than did girls in the usual care group. At the last visit, the luteal phase progesterone level was 52.9% (95% CI = 20.0% to 72.3%) lower for girls in the intervention group than for girls in the usual care group (P =.007).
  
  
  CONCLUSIONS
  Modest reductions in fat intake during puberty are associated with changes in sex hormone concentrations that are consistent with alterations in the function of the hypothalamic-pituitary-ovarian axis. Whether these changes influence breast cancer risk is currently unknown.
authors.affiliation: Fox Chase Cancer Center, Philadelphia, PA 19111, USA. jf_dorgan@fccc.edu
authors.forename: Joanne F
authors.initials: JF
authors.lastname: Dorgan
authors.forename: Sally A
authors.initials: SA
authors.lastname: Hunsberger
authors.forename: Robert P
authors.initials: RP
authors.lastname: McMahon
authors.forename: Peter O
authors.initials: PO
authors.lastname: Kwiterovich
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Lauer
authors.forename: Linda
authors.initials: L
authors.lastname: Van Horn
authors.forename: Norman L
authors.initials: NL
authors.lastname: Lasser
authors.forename: Victor J
authors.initials: VJ
authors.lastname: Stevens
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Friedman
authors.forename: Jack A
authors.initials: JA
authors.lastname: Yanovski
authors.forename: Susan F
authors.initials: SF
authors.lastname: Greenhut
authors.forename: Donald Walt
authors.initials: DW
authors.lastname: Chandler
authors.forename: Frank A
authors.initials: FA
authors.lastname: Franklin
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Barton
authors.forename: Dennis W
authors.initials: DW
authors.lastname: Buckman
authors.forename: Linda G
authors.initials: LG
authors.lastname: Snetselaar
authors.forename: Blossom H
authors.initials: BH
authors.lastname: Patterson
authors.forename: Arthur
authors.initials: A
authors.lastname: Schatzkin
authors.forename: Philip R
authors.initials: PR
authors.lastname: Taylor
mesh_terms: D000293:Adolescent; D000735:Androstenedione / Q000097:blood; D001943:Breast Neoplasms / Q000097:blood / Q000517:prevention & control*; D002648:Child; D003687:Dehydroepiandrosterone / Q000097:blood; D018752:Diet, Fat-Restricted; D004958:Estradiol / Q000097:blood; D004970:Estrone / Q000097:blood; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006266:Health Education; D006293:Health Promotion; D006801:Humans; D008572:Menarche; D009316:National Institutes of Health (U.S.); D011374:Progesterone / Q000097:blood; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013739:Testosterone / Q000097:blood; D014481:United States
chemical_list: D012739:Gonadal Steroid Hormones; D012738:Sex Hormone-Binding Globulin; D004970:Estrone; D013739:Testosterone; D000735:Androstenedione; D003687:Dehydroepiandrosterone; D011374:Progesterone; D004958:Estradiol