Vitamin D supplements might not help prevent osteoporosis in healthy adults.
A group of New Zealand researchers found that the supplements did not improve the bone mineral density in adults with a normal vitamin D level, a University of Auckland news release reported.
The team conducted a "systematic review and meta-data analysis "of how taking vitamin D supplements affected bone mineral density. They looked at data from over 4000 study subjects over 23 separate studies.
The study concluded that the supplements failed to increase bone mineral density in the "hip, spine, forearm, or in the body as a whole."
"Most healthy adults do not need vitamin D supplements" Professor Reid, who led the study, said.
"Our data suggest that the targeting of low-dose vitamin D supplements only to individuals who are likely to be deficient could free up substantial resources that could be better used elsewhere in healthcare. This systematic review provides very little evidence of an overall benefit of vitamin D supplementation on bone density. Continuing widespread use of vitamin D for osteoporosis prevention in community-dwelling adults without specific risk factors for vitamin D deficiency seems inappropriate," he said in the article published in the Lancet.
The only improvement in bone mineral density as a result of the supplements was a 0.8 percent increase at the femoral neck.
"In North America and Europe particularly, more than half the adult population have their vitamin D level assessed and take vitamin D supplements," Professor Reid said. "Some advocates have suggested that the indicator level for needing vitamin D supplements has been quite high."
"We believe that vitamin D supplements are only indicated for people with very low levels, (such as those who are frail, are confined rest-home residents, or women who are veiled, and some dark skinned people). This review study suggests that the high use of vitamin D supplements by most healthy adults is a waste of money and resources," he said.
While vitamin D supplements most likely fail to prevent osteoporosis in healthy adults, it can have significant benefits for children without access to a "conventional diet," it could succeed in preventing rickets in this case.
"Most healthy adults, especially in New Zealand, who live a normal, active life and get out regularly for activities such as walking, shopping and gardening, get vitamin D from the sun, and do not need vitamin D supplements", Professor Reid, said. "Most healthy adults, especially in New Zealand, who live a normal, active life and get out regularly for activities such as walking, shopping and gardening, get vitamin D from the sun, and do not need vitamin D supplements."
