Heart Health

The Truth About Calcium Supplements and Heart Disease

Last weekend I was appalled, once again, by Dr. Isadore Rosenfeld advising the public never take calcium supplements, because they raise the risk of heart attacks. He actually stated that you should obtain your calcium only from food, rather than supplements.

Because I found this information so outrageous, I went looking for the study (that's right, ONE STUDY) upon which this health alert was based. And, what I found is very illustrative of how the system works. Perhaps the most important piece is to remember that drug companies have a huge financial interest in discrediting natural remedies, since they perceive supplement sales as cutting into their bottom line. In the footnotes, it is disclosed that the authors of the study received support from a variety of drug companies within the prior three years.

Published in the British Medical Journal (BMJ 2010; 341:c3691) in May of 2010 and entitled "Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis," this "research" involved scanning electronic databases for eligible studies to include in their statistical analysis. The stated objective was "to investigate whether calcium supplements increase the risk of cardiovascular events." Given what the stated results are, I believe this objective reveals their bias.

Their study criteria were interesting. They selected only those studies where participants were diagnosed only with osteoporosis and were given more than 500 mg of calcium in a double-blind study (1/2 the group took a placebo instead). However, and this is KEY, no study was included where the participants were also given vitamin D, since the occurrence of adverse events drops precipitously when vitamin D is taken. No attention was paid to whether or not the study participants were concurrently taking bisphosphonates (Fosamax, Boniva, etc., commonly referred to as "osteoporosis drugs"). This is a glaring and substantive omission, as will become clear in a moment.

The conclusions reached were that "calcium supplements (without coadministered vitamin D) are associated with an increased risk of myocardial infarction . . . A reassessment of the role of calcium supplements in the management of osteoporosis is warranted." The proposed mechanism is that calcium deposits in the soft tissues of the body, increasing calcification in the coronary arteries (aka coronary artery disease, CAD).

Of course, once the popular media picked up the story, the advisory regarding vitamin D was completely dropped; and the headlines screamed, "Calcium Supplements Cause Heart Disease!"1 And, many sources recommended no one take calcium supplements.2



Let's actually analyze this information. In the first place, there are two pertinent warnings with regard to prescribing osteoporosis drugs: i) they can't be taken in the presence of low serum calcium, and ii) they cause calcification of the soft tissues, especially the esophagus, which makes it impossible for a person to swallow. Since the study participants were all diagnosed with osteoporosis as part of the meta-analysis criteria, how likely do you think it is that they were co-prescribed one of these drugs? And yet, the study design ignored these drugs as a risk factor for CAD, focusing instead only on calcium supplements. Therefore, how valid is the conclusion that the calcium supplements are causing the problem?

More interesting information is available in the magazine Life Extension, published in January of 2009.3 In that article, it was pointed out that calcium deficiency increases soft tissue calcification rates.4 This is because, when calcium is low in the blood, the body robs our bones of calcium and saturates our soft tissues. Many of our neurotransmitters are dependent on calcium channel activity, and nervous system function is the body's first priority.


Another pertinent fact is that one of the primary substances that regulate calcium balance is vitamin K. However, heart patients are routinely warned against vitamin K and given warfarin (aka Coumadin), a blood-thinning drug, which inhibits normal vitamin K function in the body. The result: rapid development of osteoporosis and arterial calcification.5, 6 Talk about unintended consequences!

The article goes on to point out that in Japan, high doses of vitamin K are often prescribed instead of warfarin to avoid these serious side effects.7, 8, 9

So, perhaps a better conclusion to our meta-analysis would have been: "A reassessment of the risk of pharmaceuticals increasing the incidence of cardiovascular events should be undertaken". How likely do you think that might be?

If you want to find out what your need is for calcium and vitamin D, call the Clinic and arrange for a customized blood panel and nutritional report.


1]  sciencedaily.com/releases/2008/01/080116193102.htm

2] foodconsumer.org/newsite/Nutrition/Minerals/calcium_ supplements_versus_myocardial_infarction_ 3107101054.html

3]  findarticles.com/p/articles/mi_6839/is_2009_Jan/ai_n31344645/?tag=content;col1

4] Hsu HH, Culley NC. Effects of dietary calcium on atherosclerosis, aortic calcification, and icterus in rabbits fed a supplemental cholesterol diet. Lipids Health Dis. 2006;516.

5]  Gage BF, Birman-Deych E, Radford MJ, Nilasena DS, Binder EF. Risk of osteoporotic fracture in elderly patients taking warfarin: results from the National Registry of Atrial Fibrillation 2. Arch Intern Med. 2006 Jan 23;166(2):241-6.

6]  Schurgers LJ, Aebert H, Vermeer C, Bultmann B, Janzen J. Oral anticoagulant treatment: friend or foe in cardiovascular disease? Blood. 2004 Nov

7]  Bugel S. Vitamin K and bone health in adult humans. Vitam Horm. 2008;78:393-416.

8] Kaneki M, Hodges SJ, Hosoi T, et al. Japanese fermented soybean food as the major determinant of the large geographic difference in circulating levels of vitamin K2: possible implications for hip-fracture risk. Nutrition. 2001 Apr;17(4):315-21.

9]  Shea MK, Dallal GE, Dawson-Hughes B, et al. Vitamin K, circulating cytokines, and bone mineral density in older men and women. Am J Clin Nutr. 2008 Aug;88(2):356-63.

You can also download associated articles as pdf files:

Effect of Calcium Supplements on Risk of Myocardial Infarction and Cardiovascular Events: Meta-Analysis


Calcium Supplements Versus Myocardial Infarction: What You Need to Know


Protection Against Arterial Calcification,Bone Loss, Cancer, and Aging!


Calcium Supplements May Increase Heart Attacks in Older Women


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