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Q: What’s this I hear about calcium supplements raising your risk of heart attack?
What you’re talking about is a study published in the July 2010 edition of the British Medical Journal. Unfortunately, the media reported the findings in a horrifying and inaccurate way. Example: “Calcium Supplements Linked to Boost in Heart Attack Risk” (Bloomburg Businessweek). With headlines like that, it’s no wonder people are worried.
Problem is, that’s not really what the study said. Here is a direct quote from the researchers: “Calcium supplements (without coadministered vitamin D) are associated with an increased risk of myocardial infarction.” A myocardial infarction is medical-speak for a heart attack.
The important note here is that these folks took calcium alone, with no supporting nutrients. And therein lies the rub.
In patients who took calcium supplements − without any supporting nutrients like vitamin D, magnesium, silicon or other synergistic nutrients − there was indeed a slight increase in heart attacks. Why? No one knows for certain, but there’s a very good working theory. Calcium and magnesium have a symbiotic relationship. In animal studies, a high-calcium diet decreases tissue levels of magnesium. Since magnesium is an essential nutrient for heart health, it’s very likely that the absence of magnesium − not the presence of calcium − is what caused the problems.
According to Alan Gaby, MD, author of the textbook Nutritional Medicine(2011), most people taking supplemental calcium should also supplement with magnesium (preferably in a 2:1 or 1:1 – calcium to magnesium – ratio). They should also take vitamin D, as well as other bone-sup-porting nutrients like silicon and vitamin K2 (both have cardio protective effects).