title: Urinary calcium response to high dose vitamin D3 with calcium supplementation in patients with multiple sclerosis.
abstract: OBJECTIVE
  To characterize the effect of vitamin D(3) intake on urinary calcium:creatinine ratios across predefined ranges of serum 25(OH)D.
  
  
  METHODS
  Patients with multiple sclerosis (n=25) received escalating doses of vitamin D(3) (4000-40,000IU/d) with calcium (1200mg/d).
  
  
  RESULTS
  Urinary calcium:creatinine was driven by increased 25(OH)D when concentrations were <75nmol/L (r=0.424, p=0.009) and >200nmol/L (r=0.281, p=0.01), but no relationship existed when 25(OH)D concentrations were 76-200nmol/L.
  
  
  CONCLUSIONS
  A "safe", physiological range of 25(OH)D concentrations is 75-200nmol/L.
authors.affiliation: University of Toronto, Department of Nutritional Sciences and Mount Sinai Hospital, Department of Pathology & Laboratory Medicine, Toronto, ON, Canada M5G 1X5. samantha.kimball@utoronto.ca
authors.forename: Samantha M
authors.initials: SM
authors.lastname: Kimball
authors.forename: Jodie M
authors.initials: JM
authors.lastname: Burton
authors.forename: Paul G
authors.initials: PG
authors.lastname: O'Connor
authors.forename: Reinhold
authors.initials: R
authors.lastname: Vieth
mesh_terms: D000328:Adult; D002118:Calcium / Q000652:urine*; D002762:Cholecalciferol / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use*; D003404:Creatinine / Q000652:urine; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D006801:Humans; D009103:Multiple Sclerosis / Q000097:blood / Q000188:drug therapy* / Q000652:urine*; D012044:Regression Analysis
chemical_list: D002762:Cholecalciferol; D003404:Creatinine; D002118:Calcium