title: Intervention with a low-fat, high-carbohydrate diet does not influence the timing of menopause.
abstract: BACKGROUND
  Later age at menopause is associated with a greater risk of breast cancer. Dietary factors may at least partially influence breast cancer risk through an effect on the age at menopause.
  
  
  OBJECTIVE
  We studied the effect of a low-fat, high-carbohydrate (LFHC) dietary intervention on the timing of menopause in women with greater risk of breast cancer.
  
  
  METHODS
  The study population included participants from an LFHC dietary intervention trial for the prevention of breast cancer in women with extensive mammographic density, a strong risk factor for breast cancer. Women who were premenopausal at baseline (n = 2611) were followed for an average of 7 y for menopause. Survival analysis was used to compare the time to menopause between the LFHC and control groups and to assess other factors associated with age at menopause.
  
  
  RESULTS
  The LFHC intervention did not affect the time to natural menopause overall (P = 0.72 for log-rank test comparing study groups; n = 699 events). An observed interaction between study group and baseline body mass index (BMI; P = 0.01) indicated that the intervention group experienced earlier menopause than did the control group when BMI was low and that a higher BMI was associated with later menopause in the intervention group only. Greater parity, weight, and education were associated with later menopause, and greater age at first birth and baseline smoking were associated with earlier menopause.
  
  
  CONCLUSIONS
  Overall, the LFHC dietary intervention did not influence the timing of menopause. Factors associated with age at menopause in this population were consistent with those reported in other populations.
authors.affiliation: Campbell Family Institute for Breast Cancer Research, Ontario Cancer Institute, University Health Network, Toronto, Canada. lmartin@uhnres.utoronto.ca
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: Martin
authors.forename: Carolyn V
authors.initials: CV
authors.lastname: Greenberg
authors.forename: Valentina
authors.initials: V
authors.lastname: Kriukov
authors.forename: Salomon
authors.initials: S
authors.lastname: Minkin
authors.forename: David J A
authors.initials: DJ
authors.lastname: Jenkins
authors.forename: Norman F
authors.initials: NF
authors.lastname: Boyd
mesh_terms: D015992:Body Mass Index; D001943:Breast Neoplasms / Q000209:etiology / Q000517:prevention & control*; D002986:Clinical Trials as Topic; D018752:Diet, Fat-Restricted; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D004041:Dietary Fats / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008327:Mammography; D008593:Menopause; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D012307:Risk Factors; D012907:Smoking; D016019:Survival Analysis; D013997:Time Factors; D015430:Weight Gain
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats