Vitamin D supplements don't help boost bone density in healthy adults, judging from a review of 23 studies that suggests the supplement should be limited to people with a documented deficiency to fight osteoporosis.
Almost half of adults older than 50 years take vitamin D, researchers led by Ian Reid of the Department of Medicine of the University of Auckland in New Zealand said in an article published in The Lancet medical journal.
A review of studies encompassing as many as 4,082 patients, most of them women, taking the supplement for an average of two years found little difference in bone density measured at key points in the skeleton, such as the hip, the forearm or the lumbar spine.