title: Antioxidant vitamin supplements and markers of bone turnover in a community sample of nonsmoking women.
abstract: BACKGROUND
  Whereas several epidemiological studies suggest that low dietary intake of vitamins C and E is linked to increased hip fracture in smokers and antioxidants (dietary and endogenous) are reduced in elderly osteoporotic women, none has demonstrated an effect of supplemental antioxidants on bone turnover.
  
  
  METHODS
  In an observational study of 533 randomly selected women, we investigated the associations among the use of antioxidant supplements, vitamins C and E, serum levels of biochemical markers of bone turnover (C-telopeptide [CTx] and bone-specific alkaline phosphatase [BSAP]), and whole body bone mineral density (BMD).
  
  
  RESULTS
  Twenty-two women were identified as current users of supplemental vitamin C or E. Duration of antioxidant supplement use was negatively associated with age-adjusted and weight-adjusted serum CTx, such that mean CTx levels (natural log transformed) were 0.022 units lower for each year of exposure. No significant differences were detected for adjusted serum BSAP or whole body BMD.
  
  
  CONCLUSIONS
  Our results suggest that antioxidant vitamin E or C supplements may suppress bone resorption in nonsmoking postmenopausal women. Coupling of bone formation and resorption may explain the absence of an effect on bone formation markers, given evidence of enhanced effects of antioxidants on osteoblast differentiation; this warrants further investigation. This work adds to the growing body of evidence that antioxidants may play a role in preventing osteoporosis.
authors.affiliation: The University of Melbourne, Department of Clinical and Biomedical Sciences, Barwon Health, Geelong, Victoria, Australia.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Pasco
authors.forename: Margaret J
authors.initials: MJ
authors.lastname: Henry
authors.forename: Laura K
authors.initials: LK
authors.lastname: Wilkinson
authors.forename: Geoffrey C
authors.initials: GC
authors.lastname: Nicholson
authors.forename: Hans G
authors.initials: HG
authors.lastname: Schneider
authors.forename: Mark A
authors.initials: MA
authors.lastname: Kotowicz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D000975:Antioxidants / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000627:therapeutic use; D001315:Australia; D015415:Biomarkers / Q000097:blood; D001862:Bone Resorption / Q000188:drug therapy* / Q000378:metabolism / Q000517:prevention & control; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy* / Q000378:metabolism / Q000517:prevention & control; D012044:Regression Analysis; D011795:Surveys and Questionnaires; D014810:Vitamin E / Q000627:therapeutic use; D016387:Women's Health
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D014810:Vitamin E; D001205:Ascorbic Acid