Posted on May 10, 2011, 6 a.m.
Newly published research has added to evidence linking calcium supplementation and an increased risk of cardiovascular events in older women.
New research has added to mounting evidence that calcium supplements increase the risk of cardiovascular events, particularly heart attacks, in older women. Professor Ian Reid of the University of Auckland and colleagues analysed data from women taking part in the Women's Health Initiative (WHI) study. The results showed that calcium supplements – whether taken with, or without vitamin D – may increase the risk of heart attack by 25%, and the risk of stroke by 15%. The findings support results of an earlier analysis which led the authors to conclude that calcium supplementation could have more risks than benefits. The authors suspect that the abrupt change in blood calcium levels that occurs after taking a calcium supplement is responsible for the adverse effect, as high blood calcium levels are linked to hardening of the arteries.
Mark J. Bolland, Andrew Grey, Alison Avenell, Greg D. Gamble, Ian R. Reid. Calcium supplements with or without vitamin D and risk of cardiovascular events: reanalysis of the Women’s Health Initiative limited access dataset and meta-analysis. BMJ. 2011;342:d2040.