Taking vitamin D with calcium supplements may significantly reduce the risk of mortality and lengthen the lives of the elderly, according to a new analysis.

The study, published in the Journal of Clinical Endocrinology and Metabolism, found that while the combination of the two supplements appeared to reduce the risk of death, taking vitamin D by itself appeared to have no benefit.

Researchers from the Aarhus University Hospital in Denmark based their findings on data from eight previous clinical trials were people were randomly given either vitamin D alone, vitamin D with calcium or a placebo.

Lead author Lars Rejnmark had collected data on more than 70,000 people who were around 70 years old, and found that over three years vitamin D alone did not reduce the risk of death, but when taken with calcium reduced mortality by 9 percent.

"This is the largest study ever performed on effects of calcium and vitamin D on mortality," said Lars Rejnmark, PhD, of Aarhus University Hospital in Denmark and lead author of 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."

Researchers noted that while taking vitamin D and calcium has been shown to reduce the risk of fractures in older people, there was no evidence that suggested that the reduction in mortality was linked to fewer bone fractures.

Recently, a study published in the May edition of Heart, linked calcium supplements to an increased risk of heart attack by 86 percent, but the risk was not increased with eating foods with calcium.

The U.S. Preventive Services Task Force on Tuesday also recommended that postmenopausal women not take low-dose calcium and vitamin D supplements daily to reduce bone fractures because the benefit was only marginal.

However, Rejnmark believes that taking the combination of supplements had an effect that went beyond bone health.

While the latest findings suggests that 151 older adults would have to take vitamin D and calcium for at least three years to prevent one death, Rejnmark belives that the 9 percent reduced mortality in the general population of the elderly id of major importance.  

"Some studies have suggested calcium (with or without vitamin D) supplements can have adverse effects on cardiovascular health," said Rejnmark. "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."

Rejnmark said that the effect is "at least as pronounced" as the benefits associated with cholesterol-lowering statins and blood pressure drugs, according to Reuters.