title: Multivitamin-multimineral supplement use and mammographic breast density.
abstract: BACKGROUND
  The effect of multivitamin-multimineral supplements on the occurrence of chronic diseases, such as breast cancer, is unclear. Breast density is increasingly used as a biomarker of breast cancer risk.
  
  
  OBJECTIVE
  The present study evaluated the association of multivitamin-multimineral supplement use with breast density.
  
  
  METHODS
  Premenopausal (n = 777) and postmenopausal (n = 783) women were recruited at the time of screening mammography. Anthropometric measurements were taken at recruitment. Demographic characteristics, behavioral factors, and health conditions were documented by telephone interview. Diet and multivitamin-multimineral and individual vitamin and mineral supplement use were assessed with a self-administered food-frequency questionnaire. Breast density from screening mammograms was measured using a computer-assisted method. Crude and adjusted means in breast density were evaluated according to multivitamin-multimineral supplement use using generalized linear models.
  
  
  RESULTS
  Current multivitamin-multimineral supplement use was reported by 21.7% of women (20.7% and 22.6% of premenopausal and postmenopausal women, respectively). Premenopausal women who were currently using multivitamin-multimineral supplements had higher adjusted mean breast density (45.5%) than past (42.9%) or never (40.2%) users (P for heterogeneity = 0.03, P for trend = 0.009). Of the current users, breast density was not related to duration of multivitamin-multimineral supplement use. In postmenopausal women, multivitamin-multimineral supplement use was not associated with breast density (P for heterogeneity = 0.53, P for trend = 0.40).
  
  
  CONCLUSIONS
  Regular use of multivitamin-multimineral supplements may be associated with higher mean breast density among premenopausal women. The relations of multivitamin-multimineral supplement use to breast density and breast cancer risk need to be clarified.
authors.affiliation: Unité de Recherche en Santé des Populations, Centre Hospitalier Affilié Universitaire de Québec, Québec, Canada.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Bérubé
authors.forename: Caroline
authors.initials: C
authors.lastname: Diorio
authors.forename: Jacques
authors.initials: J
authors.lastname: Brisson
mesh_terms: D000328:Adult; D001940:Breast / Q000187:drug effects* / Q000473:pathology*; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000209:etiology; D004032:Diet; D019587:Dietary Supplements / Q000009:adverse effects; D005260:Female; D006801:Humans; D008327:Mammography; D008875:Middle Aged; D008903:Minerals / Q000008:administration & dosage* / Q000009:adverse effects; D017698:Postmenopause; D017697:Premenopause; D011792:Quebec / Q000453:epidemiology; D012307:Risk Factors; D014815:Vitamins / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D008903:Minerals; D014815:Vitamins