title: Dietary vitamin C and bone mineral density in postmenopausal women in Washington State, USA.
abstract: OBJECTIVE
  To examine the relationship between dietary vitamin C and hip bone mineral density (BMD) in postmenopausal women.
  
  
  METHODS
  This was a cross sectional study using retrospective diet and vitamin supplement data.
  
  
  METHODS
  The Seattle area of Washington State.
  
  
  METHODS
  Screenees for a clinical trial of a drug to prevent osteoporotic fractures; 1892 women aged 55-80 years who had hip bone densitometry and osteoporosis risk factor information.
  
  
  RESULTS
  Mean energy adjusted dietary intake of vitamin C was 113 mg/day; including supplement use, mean intake was 407 mg/day. There were no differences in BMD according to diet-only vitamin C intake or combined dietary and supplemental vitamin C intake. Longer duration of vitamin C supplement use was associated with higher BMD in women who had not used oestrogen replacement therapy (trend p = 0.02) and among women aged 55-64 years (trend p = 0.01). Women aged 55-64 years who used vitamin C supplements for > or = 10 years had a higher BMD than non-users aged 55-64 years (multivariate adjusted mean BMD 0.699 (0.017) g/cm2 versus 0.655 (0.007) g/cm2, p = 0.02). Benefits were not evident in older age groups or in women who had used oestrogen in the past. Frequent intake of foods rich in vitamin C was not associated with BMD.
  
  
  CONCLUSIONS
  There was no evidence that vitamin C from the diet was associated with BMD, although long term use of vitamin C supplements was associated with a higher BMD in the early postmenopausal years and among never users of oestrogen.
authors.affiliation: Center for Health Studies, Group Health Cooperative of Puget Sound, Seattle, Washington, USA.
authors.forename: S G
authors.initials: SG
authors.lastname: Leveille
authors.forename: A Z
authors.initials: AZ
authors.lastname: LaCroix
authors.forename: T D
authors.initials: TD
authors.lastname: Koepsell
authors.forename: S A
authors.initials: SA
authors.lastname: Beresford
authors.forename: G
authors.initials: G
authors.lastname: Van Belle
authors.forename: D M
authors.initials: DM
authors.lastname: Buchner
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001205:Ascorbic Acid / Q000008:administration & dosage* / Q000494:pharmacology; D015519:Bone Density / Q000187:drug effects*; D003430:Cross-Sectional Studies; D004334:Drug Administration Schedule; D005260:Female; D005272:Femur Neck / Q000502:physiology; D005638:Fruit; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause / Q000502:physiology*; D012189:Retrospective Studies; D014675:Vegetables; D014861:Washington / Q000453:epidemiology
chemical_list: D001205:Ascorbic Acid