Want to live longer? Who doesn’t! Why some people live to be over 100 years old while others only live half that long is currently a mystery. But a recent review*of data collected on over 70,000 adults revealed an interesting trend: people who take vitamin D and calcium supplements appear to have a lower overall risk of dying.
The researchers, whose results are published in Journal of Clinical Endocrinology, found that older people who were given the supplements were 9 percent less likely to die over three years than those given placebo pills. Interestingly, it appears to be the combination of vitamin D and calcium that increases longevity; vitamin D alone had no impact on death rates.
While a 9 percent reduction in death risk over a three-year period might sound insignificant, lead researcher Lars Rejnmark indicates that the effect is comparable to the benefits linked to cholesterol-lowering statins and blood pressure drugs.
Rejnmark and his colleagues combined the results from eight clinical trials involving more than 70,000 older adults, mostly women. In each of the trials they reviewed, people were randomly assigned to take vitamin D or a placebo. Some studies used a combination of vitamin D and calcium.
The doses varied, but most trials used a daily vitamin D dose of 10 to 20 micrograms. In the United States, health officials suggest that most adults get 15 micrograms (or 600 IU) of vitamin D per day, while people older than 70 should aim to get 20 micrograms.
In trials that used calcium, the dose was 1,000 milligrams per day. In the U.S., women older than 50, and everyone over 70, are told to get 1,200 milligrams of calcium each day.
So what accounts for this association? The researchers are not certain. They suspected that it might be due to the nutrients’ ability to prevent bone fractures, a common cause of death in the elderly. But when they factored in hip and spine fractures they did not account for the reduced mortality.
Another possibility is that the supplements reduced the risk of cancer. Rejnmark said there's some evidence that calcium and vitamin D may lower the odds getting of colon cancer, but the evidence is not yet "firm". For now, he said, the findings supported getting the recommended amounts of vitamin D and calcium.