title: Assessing vitamin D status.
abstract: OBJECTIVE
  To characterize methods evaluating and to summarize studies linking various serum 25-hydroxyvitamin D [25(OH)D] concentrations with health status.
  
  
  RESULTS
  Elucidation of the cell-biologic mechanism of vitamin D action, and numerous clinical trials and observational studies relating vitamin D status to health and disease.
  
  
  CONCLUSIONS
  The distinction between deficiency and insufficiency is not useful or necessary. Serum 25(OH)D values below 120  nmol/l (48  ng/ml) are associated with preventable disease and are therefore indicative of deficiency. The upper limit of the normal range can be set at 225  nmol/l (90  ng/ml), although toxicity is rare below 500  nmol/l (200  ng/ml).
authors.affiliation: Creighton University, Omaha, Nebraska 68131, USA. rheaney@creighton.edu
authors.forename: Robert P
authors.initials: RP
authors.lastname: Heaney
mesh_terms: D006304:Health Status; D006801:Humans; D015596:Nutrition Assessment; D009752:Nutritional Status; D012016:Reference Values; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood* / Q000633:toxicity; D014808:Vitamin D Deficiency / Q000097:blood* / Q000150:complications / Q000175:diagnosis
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D