Increased calcium intakes may reduce mortality risk

A new study from Canada suggests that taking up to 1,000 mg of calcium per day may lower women’s mortality risk.

The observational study estimated calcium intakes and monitored health of 9,033 men and women over
12 years (1). The study results showed that women with daily calcium intakes of up to 1,000 mg had a 22% reduction in mortality risk compared with women who had low intake. Longer lifespans among women were observed regardless of the source of the calcium: dairy foods, non-dairy foods or supplements. No statistical benefit of higher calcium intake was observed for men.

The researchers commented that beyond potentially life-prolonging effects, adequate calcium and vitamin D intakes are necessary to maintain bone health and treat osteoporosis. Their recommendation is to assess dietary intake to assure that calcium and vitamin D requirements are being met and consider supplemen-tation if necessary. The benefits reported in the study could stem from women generally using more supple-ments, which brings their calcium status up to normal and optimal levels, while men tend to get calcium exclusively from their diet. Earlier research has linked increased calcium intake to a better balance of blood fats, lower risk of high blood pressure, better bone metabolism and bowel health.

There have been conflicting results from studies in recent years about the benefits and possible harms of taking calcium supplements, especially more than 1,000 mg per day. Some scientists suggested that mega doses of calcium circulating in the blood could have a “flooding effect” which may lead to hardening of the arteries and heart attacks. Thus, calcium should be taken in small amounts spread throughout the day, so it is absorbed slowly. UK’s Food Standards Agency recommends adults ingest 700 mg of calcium per day.

1. Goltzman D. et al. Calcium and vitamin D intake and mortality: Results from the Canadian Multi-centre Osteoporosis Study. Journal of Clinical Endocrinology & Metabolism. Published online May 2013.