Calcium Supplements and Heart Attack Risk
It’s been all over the news for years: calcium supplements may, in fact, increase your risk of a heart attack.
Which is pretty alarming considering the fact that everyone should be taking a calcium supplement. Do we really have to choose between osteoporosis and a heart attack?
What’s the real story? And is there a safer solution?
Well, first, lets take a look at the findings. The actual study1 was published in the British Medical Journal July 29, 2010. It’s what’s called a meta-analysis, meaning rather than conducting a study with their own participants the researchers gathered data from multiple studies conducted by others and analyzed the data for things the original researchers may or may not have been looking at.
15 separate studies were analyzed. To be included each study had to have at least 100 participants with a mean age of at least 40 and to compare calcium supplementation of at least 500 mg a day with a placebo. There were a total of 11,923 participants who were studied for an average of 4 years.
Of the nearly 12,000 participants, 309 of those taking calcium had heart attacks during the course of the study, while only 241 of those on the placebo had one. The researchers concluded that those taking the calcium supplement had between 27% and 31% greater chance of a heart attack than those on the placebo.
Some things to note about this study: The researchers were selective about which studies they analyzed. They did NOT include any studies in which the subjects took calcium with other supporting ingredients, such as vitamin D or magnesium – both of which are crucial (along with a few others) for proper calcium absorption.
Also, all of the studies used either calcium carbonate or citrate- none used the better-absorbed, safer calcium citrate malate.
These Findings Aren’t Unique
But this is not the first time this kind of finding has been published. Three of the researchers on this team were part of another team that conducted a separate study2, also published in the BMJ back in 2008. This study was not included in the one above.
They had a group of 1471 postmenopausal women and divided them into two groups. 732 of them were given 1,000 MG per day of Citracal brand calcium citrate, and 739 were given a placebo. The women were assessed every six months for five years.
Starting at about 30 months out, the women in the Citracal group began having more heart attacks. By the time the study was over, 31 women in the Citracal group had had a total of 45 Myocardial Infarction “events.” In the placebo group only 14 women had a total of 19 events.
One of the researchers on both studies, Professor Ian R Reid said, “We calculate that for every 1,000 people treated with calcium for 5 years, it will lead to four additional myocardial infarctions, four additional strokes, and two additional deaths, while preventing three fractures.”
What Is It About Calcium Supplements That Increase The Risk Of Heart Attack?
The authors of these studies suggest that the problem is that calcium supplements lead to higher levels of calcium in the blood, and that elevated levels of calcium in the blood have also been found to lead to higher incidences of heart attacks. They speculate that this elevated blood calcium leads to calcification or hardening of the arteries and heart disease.
In other words, when you take a caclium supplement that only floats around in your bloodstream it causes much more harm than good.
So What Does This Mean For You?
First of all, the studies above were all conducted using calcium in the form of carbonate or citrate. No studies with calcium citrate malate were included, and so far no studies that have been conducted on this form have found heart risk.
Secondly, it’s very well known that calcium in any form needs certain supporting ingredients to be best utilized by the body. Vitamin D, especially is not only essential for calcium absorption3, it’s been shown in studies to reduce the risk of cardiovascular events4. It’s significant that none of the studies showing the increased risks included vitamin D supplements.
Magnesium has been referred to as “Nature’s Physiologic Calcium Blocker5” because it blocks the entry of calcium into heart cells and the smooth muscle cells of blood vessels. With or without calcium supplementation magnesium has been shown to have a positive effect on heart disease6.
Most importantly, Vitamin K may well be the key. It is the substance that helps move calcium out of arteries and into bones7. Further, it’s been found to reduce existing calcium buildup in arteries by 37% in only 6 weeks8.
Protecting Your Bones And Your Heart
We all know the media loves to sensationalize. So it’s really no surprise that the headlines focused on the dangers of calcium supplements – and in doing so only told half the story. Calcium supplements taken alone, with no supporting ingredients lead to an increased risk of heart attack.
There is a safer alternative. Taking into account not just bone health but documented risks to heart and vascular health, the science seems to suggest you take a calcium supplement in the form of Calcium Citramate, and that it be supported with proper amounts of vitamin D, magnesium, vitamin K and other supporting ingredients.
To learn more about the supplement we recommend click here.
1Bolland, Mark J., et al. “Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis.” Bmj 341 (2010): c3691.
2Bolland, Mark J., et al. “Vascular events in healthy older women receiving calcium supplementation: randomised controlled trial.” Bmj 336.7638 (2008): 262-266
3Wasserman, R. H. “Vitamin D and the dual processes of intestinal calcium absorption.” The Journal of nutrition 134.11 (2004): 3137-3139.
4Wang, Lu, et al. “Systematic review: vitamin D and calcium supplementation in prevention of cardiovascular events.” Annals of internal medicine152.5 (2010): 315-323.
5Iseri, Lloyd T., and James H. French. “Magnesium: nature’s physiologic calcium blocker.” American heart journal 108.1 (1984): 188-193.
6Ford, Earl S. “Serum magnesium and ischaemic heart disease: findings from a national sample of US adults.” International journal of epidemiology 28.4 (1999): 645-651.
7Vermeer, C., K-SG Jie, and M. H. J. Knapen. “Role of vitamin K in bone metabolism.” Annual review of nutrition 15.1 (1995): 1-21.
8Schurgers, Leon J., et al. “Regression of induced medical elastocalcinosis by high intake of vitamin K in rats.” Blood 109.7 (2007): 2823-2831.