title: Calcium and vitamin D supplementation: state of the art for daily practice.
abstract: BACKGROUND
  Calcium and vitamin D play an essential role in bone metabolism but deficiency and/or inadequate intake are common.
  
  
  OBJECTIVE
  To describe a practical approach based on the literature regarding clinically important aspects of calcium and vitamin D supplementation.
  
  
  METHODS
  A systematic evaluation of relevant literature in Medline was conducted. We included physiological studies, publications on relevant guidelines, meta-analysis, randomized clinical trials, and cohort studies.
  
  
  RESULTS
  An adequate calcium intake and vitamin D supplementation is recommended in most guidelines xon fracture prevention. Daily supplementation with 800 IU is advocated in most guidelines, appears to be safe, and with this approach it is generally not necessary to determine vitamin D levels. There are no data on additional effects of loading doses of vitamin D on fracture or fall prevention. Calcium supplementation should be tailored to the patient's need: usually 500 mg per day is required. The intestinal absorption of calcium citrate is approximately 24% better than that of calcium carbonate independent of intake with meals. Data on difference between calcium absorption with calcium carbonate compared to calcium citrate with simultaneous use of proton pump inhibitors are lacking. Concern has arisen about a possible link between calcium supplementation and an increased risk of myocardial infarction. Probably only well-designed prospective randomized controlled trials will be able to allow definite conclusions on this subject.
  
  
  CONCLUSIONS
  Daily supplementation with 800 IU vitamin D is a practical and safe strategy without the need for prior determination of vitamin D levels. Calcium supplementation should be tailored to the patient's need based on total daily dietary calcium intake. In most patients 500 mg per day is required to achieve a total intake of 1,200 mg, or in some 1,000 mg per day. More calcium is absorbed from calcium citrate compared to calcium carbonate.
authors.affiliation: Department of Internal Medicine, VieCuri Medical Centre for North Limburg, Venlo, The Netherlands.
authors.forename: Robert Y
authors.initials: RY
authors.lastname: van der Velde
authors.affiliation: Department of Geriatric Medicine, Expertise Centre for Pharmacotherapy in the Elderly, Ephor-UMC Utrecht, The Netherlands.
authors.forename: Jacobus R B J
authors.initials: JR
authors.lastname: Brouwers
authors.affiliation: Department of Rheumatology, CAPHRI, Maastricht UMC, Maastricht, The Netherlands ; Biomedical Research Centre, University of Hasselt, Diepenbeek, Belgium.
authors.forename: Piet P
authors.initials: PP
authors.lastname: Geusens
authors.affiliation: Department of Rheumatology, VU Medical Centre, Amsterdam, The Netherlands.
authors.forename: Willem F
authors.initials: WF
authors.lastname: Lems
authors.affiliation: Department of Internal Medicine, VieCuri Medical Centre for North Limburg, Venlo, The Netherlands ; Department of Rheumatology, CAPHRI, Maastricht UMC, Maastricht, The Netherlands ; Biomedical Research Centre, University of Hasselt, Diepenbeek, Belgium.
authors.forename: Joop P W
authors.initials: JP
authors.lastname: van den Bergh
keywords: calcium absorption; cardiovascular risk; fall prevention; fracture prevention; vitamin D supplementation