We have read and reviewed the report on observational research, published Oct. 10 in the Journal of the American Heart Association, which concludes that taking calcium in the form of supplements may raise the risk of atherosclerosis as assessed by calcium deposits in the coronary arteries, although a diet high in calcium-rich foods appears to be protective.
As the authors note, since their study is not a randomized trial, their work only documents an association between calcium supplements and coronary calcium deposits, and does not prove cause and effect. They also state, “Our findings should be considered hypothesis-generating to stimulate further investigation in this area.” Importantly, these investigators did not examine the relationship between calcium intake or calcium supplement use and heart attacks or other clinical manifestations of coronary atherosclerosis.
NOF and the American Society of Preventative Cardiology (ASPC) convened an Expert Panel to evaluate the effects on cardiovascular disease of dietary and supplemental calcium based on the existing peer-reviewed scientific literature as of May 1, 2016. The Expert Panel considered the findings of the accompanying updated Evidence Report provided by an independent Evidence Review Team at Tufts University as well as other recent animal/mechanistic study. This Evidence Report and NOF and ASPC’s joint position statement is due to be published in the Annals of Internal Medicine at the end of October 2016.
The Evidence Report and Expert Panel conclude that based upon the best available evidence to date, primarily from randomized trials and not observational data, calcium intake from food and supplements that does not exceed 2000-2500 mg/d, should be considered safe from a cardiovascular standpoint. Obtaining calcium from food sources is preferred, but supplemental calcium can be safely used to make up any shortfalls in intake. Discontinuation of supplemental calcium for safety reasons is not necessary and may be detrimental to bone health in situations where intake from food is suboptimal.
Further details about our Position Statement and the Evidence Report will be published in the near future.