title: Effect of vitamin A on fracture risk.
abstract: OBJECTIVE
  To describe current data evaluating the effect of vitamin A intake on fracture risk.
  
  
  METHODS
  A literature search using MEDLINE (1966-March 2005) was conducted using the search terms bone density, fractures, osteoporosis, retinol, and vitamin A to identify published studies evaluating the effects of vitamin A on bone.
  
  
  RESULTS
  Studies evaluating vitamin A consumption and fracture risk were reviewed. Current data suggest a potential inverse relationship between excess vitamin A consumption and bone mineral density leading to an increased risk for fracture.
  
  
  CONCLUSIONS
  Although current data are limited, consumption of large amounts of vitamin A may be associated with decreased bone mineral density and increased fracture risk. Until further information is available, patients should be made aware of the potential risks of consuming vitamin A in amounts that exceed the recommended dietary allowance. Further research is needed to clarify the relationship between vitamin A and fracture risk.
authors.affiliation: Purdue University/Clarian Health Partners, Indianapolis, IN 46202, USA. hjackson@clarian.org
authors.forename: Heather A
authors.initials: HA
authors.lastname: Jackson
authors.forename: Amy Heck
authors.initials: AH
authors.lastname: Sheehan
mesh_terms: D015519:Bone Density; D050723:Fractures, Bone / Q000453:epidemiology*; D006801:Humans; D010024:Osteoporosis / Q000188:drug therapy; D018570:Risk Assessment; D014801:Vitamin A / Q000009:adverse effects*; D014815:Vitamins / Q000009:adverse effects*
chemical_list: D014815:Vitamins; D014801:Vitamin A