Calcium is critical for reasons we all know about, but we don’t necessarily know about what too much calcium can do—especially for women. High intakes of the mineral are linked with a higher risk of death from all causes, and from heart disease in particular.
We are all told to think about our calcium intake and, because the message has gotten out, 60% of middle-aged and older women take calcium supplements in the U.S. Taking these supplements was deemed the best health advice, though recently we have come to learn that overdoing it with calcium puts one at risk of heart disease and stroke. Still, few studies have looked into this matter.
In Sweden, researchers studied over 61,000 women for an average of 19 years, taking data from death registries and data on supplements and diets. The lowest calcium intake was 572 milligrams (mg) a day (e.g. five slices of cheese) and the highest was 2,137 mg.
Over the two decades of follow-up, nearly 12,000 women died: 3,862 of them (32%) from cardiovascular disease; 1,932 (16%) from other forms of heart disease; and 1,100 (eight percent) from stroke. Those with a dietary intake of calcium—over 1,400 mg a day—had the highest rates of all-cause death and heart disease. Conversely, women getting less than 600 mg a day also faced higher death rates.
The right amount of calcium lies in the middle. Women with a high intake (over 1,400 mg/day) were more than twice as likely to die compared with women with a 600–999 mg/day calcium intake. What happens is that diets very low or very high in calcium can start dangerously fluctuating blood levels of calcium over time.
But the main problem is in adding supplements when a person may not have to. The researchers suggest that, to prevent bone fractures, women with a low intake of calcium should take supplements. But people consuming satisfactory amounts of calcium may not need supplements at all.
So before you go on calcium supplements, consider your diet. Are you getting around 1,000 mg through it alone? Then you might be just fine.
Sources for Today’s Articles:
Why Women Shouldn’t Go Overboard with Calcium
“Risk of cardiovascular death doubled in women with high calcium intake: High risk only in those taking supplements as well,” British Medical Journal, published online February 12, 2013.