Researchers analysed data from 68,517 people, average age 70, who took part in seven studies that looked at the effect vitamin D or vitamin D plus calcium had on reducing fractures.
The analysis revealed that vitamin D given alone in doses of 10 micrograms to 20 micrograms per day doesn't prevent fractures. However, calcium and vitamin D given together reduce the risk of hip fractures, total fractures and possibly vertebral fractures.
The study, published online in January 2012 in the British Medical Journal called for additional studies of vitamin D, especially vitamin D given at higher doses without calcium.
There's a growing consensus that a combination of calcium and vitamin D is more effective than vitamin D alone in preventing nonvertebral fractures, Opinder Sahota, of Queen's Medical Center in Nottingham, England, wrote in an accompanying editorial.
Further research is need to determine the most effective dose, treatment duration and method of taking the calcium/vitamin D combination, Sahota said.
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