8 April 2014

Vitamin D does not help you live longer

Despite claims that vitamin D could be the new cure-all, new research from the University of Cambridge which examined data from nearly 100 studies has shown that vitamin D supplementation, when administered alone, does not reduce mortality among older adults.

Previous research had observed that lower levels of vitamin D in the blood are associated with a number of different diseases, including multiple sclerosis, cancer and cardiovascular disease. As it was unclear whether vitamin D supplementation when given alone (that is, not adminstered together with other interventions such as calcium) would reduce the risk of deaths from various causes, researchers analysed the results of 73 observational cohort studies and 22 randomised trials of both naturally circulating vitamin D and supplements (either D2 or D3). 

The analysis reinforced the observational associations of lower levels of circulating vitamin D concentrations with deaths from cardiovascular, cancer, as well as other causes, but also found that vitamin D supplements in the trials, overall, did not reduce the risk of all-cause mortality significantly.
However, when researchers looked deeper, they did find that vitamin D3 alone reduced mortality by 11%, and stress that additional research on healthy populations is needed.

The research was published in the British Medical Journal (BMJ), and conducted by an international team of researchers that was co-led by Dr Rajiv Chowdhury at the University of Cambridge’s Department of Public Health and Primary Care. 

Dr Chowdhury said: “Before any recommendation of widespread supplementations with vitamin D3, it is, however, essential that further clinical investigations are conducted into the optimal dosage and safety. 

"It will also be important to examine whether D2 or D3 alone may indeed have different effects on the risk of death in different populations since the current trials were essentially based in elderly high risk populations with a variety of baseline diseases and any beneficial effects on healthy general populations are not yet known."

Read the original press release here.