The study – published in the Journal of Clinical Endocrinology and Metabolism – reviews eight clinical trials with data from over 1,000 participants, finding that vitamin D, when taken with calcium, can reduce the rate of mortality in seniors – therefore providing a possible means of increasing life expectancy.
"This is the largest study ever performed on effects of calcium and vitamin D on mortality," said Lars Rejnmark, PhD, of Aarhus University Hospital, Denmark – who led the study.
"Our results showed reduced mortality in elderly patients using vitamin D supplements in combination with calcium, but these results were not found in patients on vitamin D alone," he explained.
The new study used pooled data from eight randomized controlled trials with more than 1,000 participants each to assess mortality among participants randomised to either vitamin D alone or vitamin D with calcium.
The data set was comprised of nearly 90% women, with an average age of 70 years.
“Vitamin D alone did not affect mortality, but risk of death was reduced if vitamin D was given with calcium,” revealed the researchers.
The findings from the study also found that the reduced mortality was not due to a lower number of fractures – but represents a beneficial effect beyond the reduced fracture risk.
Rejnmark noted that some recent studies have suggested calcium supplementation – both with and without vitamin D – can have adverse effects on cardiovascular health.
For example, researchers recently warned that calcium supplements should be ‘taken with caution’ after research published in Heart suggested consumption of the supplements could double the risk of heart attack incidence.
Another study, published in the British Medical Journal last year, suggested that calcium supplements – when taken with or without vitamin D – could increase the risk of heart attack by 25 per cent, and the risk of stroke by 15 per cent.
"Although our study does not rule out such effects, we found that calcium with vitamin D supplementation to elderly participants is overall not harmful to survival, and may have beneficial effects on general health,” said Rejnmark.
Source: Journal of Clinical Endocrinology and Metabolism
Published online ahead of print, doi: 10.1210/jc.2011-3328
“Vitamin D with Calcium Reduces Mortality: Patient Level Pooled Analysis of 70,528 Patients from Eight Major Vitamin D Trials”
Authors: L. Rejnmark, A. Avenell, T. Masud, F. Anderson, H.E. Meyer, K.M. Sanders, et al