title: Dietary isoflavones and bone mineral density during midlife and the menopausal transition: cross-sectional and longitudinal results from the Study of Women's Health Across the Nation Phytoestrogen Study.
abstract: OBJECTIVE
  This study aims to examine cross-sectional and longitudinal relations between dietary intake of isoflavones and bone mineral density (BMD) at the lumbar spine (LS) and femoral neck (FN) in black, white, Chinese, and Japanese women during the menopausal transition.
  
  
  METHODS
  We tested whether tertiles of isoflavone intake were associated with baseline BMD when all women were premenopausal or early perimenopausal. To analyze whether isoflavone intake was associated with longitudinal BMD, we fitted piecewise linear models to repeated measurements of baseline-normalized LS or FN BMD as functions of time before or after the final menstrual period (FMP) date.
  
  
  RESULTS
  Multiply adjusted mean FN BMD values of premenopausal Japanese women were monotonically positively related to isoflavone consumption (P for trend = 0.0003). Otherwise, no statistically significant baseline associations were observed. During the period of 1 year before the FMP through 5 years after the FMP, all participants lost LS and FN BMD. Loss was unrelated to isoflavone intake, except for Japanese women during the period of 1 year before the FMP to 2 years after the FMP: higher tertiles of isoflavone intake were associated with greater annual LS BMD loss rates (P for trend = 0.01) and FN loss rates (P for trend = 0.04).
  
  
  CONCLUSIONS
  In Japanese women, higher isoflavone intake is associated with higher peak FN BMD but also with greater rates of LS and FN BMD loss during the menopausal transition. Results for the other racial/ethnic groups did not support a relation between dietary intake of isoflavones and either peak BMD or BMD loss during the menopausal transition.
authors.affiliation: From the 1Division of Geriatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA; 2Department of Preventive and Behavioral Medicine, University of Massachusetts Medical School, Worcester, MA; 3Department of Epidemiology and Preventive Medicine, University of California at Davis, Davis, CA; and 4Department of Obstetrics and Gynecology, UC Davis Medical Center, Davis, CA.
authors.forename: Gail A
authors.initials: GA
authors.lastname: Greendale
authors.forename: Chi-Hong
authors.initials: CH
authors.lastname: Tseng
authors.forename: Weijuan
authors.initials: W
authors.lastname: Han
authors.forename: Mei-Hua
authors.initials: MH
authors.lastname: Huang
authors.forename: Katherine
authors.initials: K
authors.lastname: Leung
authors.forename: Sybil
authors.initials: S
authors.lastname: Crawford
authors.forename: Ellen B
authors.initials: EB
authors.lastname: Gold
authors.forename: L Elaine
authors.initials: LE
authors.lastname: Waetjen
authors.forename: Arun S
authors.initials: AS
authors.lastname: Karlamangla
mesh_terms: D000328:Adult; D001213:Asian / Q000706:statistics & numerical data; D044383:Black People / Q000706:statistics & numerical data; D015519:Bone Density / Q000187:drug effects*; D002681:China / Q000208:ethnology; D003430:Cross-Sectional Studies; D002149:Energy Intake / Q000208:ethnology; D005260:Female; D005272:Femur Neck; D006801:Humans; D007529:Isoflavones / Q000008:administration & dosage* / Q000032:analysis*; D007564:Japan / Q000208:ethnology; D008137:Longitudinal Studies; D008159:Lumbar Vertebrae; D008598:Menstruation; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000208:ethnology; D047648:Perimenopause / Q000208:ethnology*; D014481:United States; D044465:White People / Q000706:statistics & numerical data; D001741:Black or African American
chemical_list: D007529:Isoflavones