By Stephen Daniells
Feburary 25, 2010

Intakes of calcium above the recommended daily levels may reduce the risk of dying from heart disease and cancer by 25 per cent, says a new study from Sweden.

Average daily intakes of 1,953 m of the mineral were also associated with a non-significant lower risk of mortality from only heart disease, compared to average daily intakes of 990 mg per day, according to findings published in the American Journal of Epidemiology.

Recommended daily intakes of calcium for people between 19 and 50 years of age are 1,000 mg for both men and women, according to the US National Institutes of Health (NIH).

On the other hand, intakes of magnesium were not associated with mortality from all-causes, heart disease or cancer, report researchers led by Alicja Wolk from the Karolinska Institutet.

Wolk and her co-workers analysed data from 23,366 Swedish men aged between 45 79, non of whom used dietary supplements. Between 1998 and the end of 2007, they documented 2,358 deaths from all causes, which included 819 deaths from cardiovascular disease and 738 from cancer.

The highest average intakes, almost double the recommended levels, were associated with a 25 per cent reduction in so-called all-cause mortality, compared with the lowest average intakes, said the researchers.

Magnesium intakes up to about 523 milligrams per day were not associated with any modifications to the risk of all-cause, CVD, or cancer mortality, they added.

“This population-based, prospective study of men with relatively high intakes of dietary calcium and magnesium showed that intake of calcium above that recommended daily may reduce all-cause mortality,” they concluded.

Blood pressure link

The findings relating to heart disease appear to be inline with findings from other studies, which have reported that the mineral may lower blood pressure and reduced the risk of hypertension. Such a link is controversial, however, with a Cochrane review published in 2006 reporting that the associations were weak.

Various studies have also linked the mineral to reduced risks of colorectal (when combined with vitamin D) and prostate cancer. However, the new study found no significant relationship between calcium intakes and the risk of mortality from cancer.

Too much of a good thing

According to the NIH’s Office of Dietary Supplements, excessive calcium intakes may impair kidney function and detrimentally affect the absorption of other minerals.

The upper tolerable limit for the mineral is 2,500 milligrams, and excessive calcium intakes rarely occur from dietary or supplemental calcium intakes, said the NIH ODS.