Researchers found that taking vitamin D supplements do not improve the bone mineral density in all adults.

Bone mineral density is a measure of bone strength and measures the amount of bone mineral present at different sites in the body.

The measure is often considered as an indicator for the risk of osteoporosis, which can lead to an increased risk of fracture.

The research team analyzed the results after observing 23 various studies among nearly 4,000 healthy adults with an average age of 59, according to the findings published in The Lancet.

The study unveils that use of vitamin D pills can ward off osteoporosis only in those older people who have the vitamin deficiency.

"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 health care," said the study leader, professor Ian Reid of the University of Auckland in New Zealand.

The results indicate that most healthy adults do not need vitamin D supplements, he emphasized.

Vitamin D can be supplied from sunlight on the skin, but it is also found in certain foods like oily fish, cheese, eggs and breakfast cereals.

The experts also warn that taking too much vitamin D in the form of supplements can be harmful because calcium can build up and damage the kidneys.

They also say, however, supplementation to prevent osteoporosis in healthy older people is not warranted, “maintenance of vitamin D stores in the elderly combined with sufficient dietary calcium consumption remains an effective approach for prevention of hip fractures."

The Natural Products Association (NPA) contested the results. Dr. Cara Welch, senior vice president of scientific and regulatory affairs, commented on review findings that say vitamin D for osteoporosis prevention is inappropriate: “It’s common knowledge that the beneficial effect of vitamin D in osteoporosis prevention occurs when the supplementation is vitamin D plus calcium. This meta-analysis misleads consumers by only looking at half the equation.

"The beneficial effect of vitamin D and calcium is due to the fact they work in tandem, and examining the outcomes of just vitamin D caused the researchers to start with a weak premise. In fact, the Food and Drug Administration has an approved health claim for vitamin D and calcium regarding osteoporosis.

"This review does not do an adequate job of giving the public the whole story, and it draws a conclusion that should not discourage consumers from taking vitamin D. A deficiency in vitamin D is not uncommon and can be difficult to overcome with diet alone. NPA believes that dietary supplementation is both safe and effective for those who fall under this category. The Institute of Medicine’s recommended dietary allowances are 600-800 IU/day for adults over 50 years of age.

"NPA recommends that consumers discuss their dietary supplement regimen with their health care professional.”