The use of vitamin D supplements has previously been thought to help improve bone strength and was particularly popular among women who aimed to keep osteoporosis at bay. However, a new study says there are no benefits to warrant the connection between the two.

A new meta-analysis from New Zealand of more than 4,000 healthy adults concludes that supplements fail to increase the density of bone at the hip, spine, forearm, or in the body as a whole. Thousands of women around the world take supplements which are either prescribed by their doctor for osteoporosis or bought over the counter as 'bone insurance'.

Osteoporosis is condition in which the bones become brittle and fragile from loss of tissue, typically as a result of hormonal changes, or calcium deficiency.

Prof Ian Reid of the University of Auckland in New Zealand, who led the study, said: "Most healthy adults do not need vitamin D supplements.

"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."

Vitamin D is crucial for the immune system, strong healthy bones and teeth, and the absorption of calcium, and there is growing evidence that vitamin D deficiency may be responsible for triggering a range of diseases, including several cancers.

These new findings conflict with some reviews showing a benefit of vitamin D on fracture risk, the authors note. However, those reviews include studies in which the intervention is a combination of vitamin D and calcium, and fracture risk cannot be distinguished for vitamin D alone.

However, such claims should not discourage healthy people from taking vitamin D for all the possible benefits, says the Council for Responsible Nutrition.

Prof Reid and colleagues conducted a systematic review of 23 randomized trials examining the effects of using vitamin D supplements to boost bone mineral density in 4,082 healthy adults aged 59 on average up to July 2012.