Effect of vitamin A on fracture risk
Heather A Jackson1, Amy Heck Sheehan
1Purdue University/Clarian Health Partners, Indianapolis, IN 46202, USA. hjackson@clarian.org
Objective:
To describe current data evaluating the effect of vitamin A intake on fracture risk.
Data Sources:
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.
Data Synthesis:
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.
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