Several weeks ago we reported on a fascinating article published in the British journal BMJ. It was a meta-analysis of 11 studies that included over 12,000 people over the age of 40. The investigators were trying to sort out the benefits and risks of calcium supplementation for the cardiovascular system. Some previous studies had suggested that high calcium intake from the diet was beneficial, but others showed that calcium supplements increased the risk for calcification of blood vessels.
The results of this evaluation created quite a controversy. People have been told for so long that calcium supplements are critical for good health that they have a hard time imagining there could be a downside. People also wanted more information. Here is just one example. We also encourage you to read the original research in the BMJ.
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I appreciate these updates and do not expect an in-depth article, however, your reporting is pretty shallow and sometimes alarmist. There is nothing here to gauge the definition of how much is “too much” calcium. What is the specific age range? What dosage? How often?
Does culture make a difference i.e., British, American, Asian, Mediterranean diets and lifestyles are all very different. And what qualifies you to “suggest” getting calcium more from food (a “given” by the way) or to discontinue taking supplements which might be ill-advised for at-risk populations like older women!
I just don’t think medical “sound bites” are very valuable. I used to enjoy listening to your radio program, but I have come to see this website as more of a catalog to promote your products and less a source of serious and helpful health information.

PEOPLE’S PHARMACY RESPONSE:
It is not surprising that so many visitors to this website would find our brief overview of the BMJ article disturbing. After all, Americans have been told for decades to take calcium to build strong bones. The trouble with that advice, however, was that it was not based on science.
If one really looks at the research, and there is an amazing amount of it, you will discover that the data demonstrating that calcium can be helpful in preventing fractures is exceptionally weak. Over the years more than 140 studies have examined the effects of calcium on fracture risk. About one third suggest benefit. Over half show no reduced risk (the rest were inconclusive).
Let’s take a look at epidemiology. In countries where people consume a LOT of milk, dairy products AND calcium supplements (Scandinavia, the United States and the UK), hip fractures are very common. In countries where milk and dairy consumption (and calcium pills) is low (Africa, China, New Guinea and Iran), hip fracture rate is much lower.
What about vitamin D? Many of the comments on this site have pointed out that the BMJ research was flawed because it did not include studies of vitamin D added to calcium. The meta-analysis could only analyze the studies that were available. Most of the big studies were done with calcium alone. The doses of calcium that were employed in the various studies ranged from 500 mg of calcium carbonate to 1,400 mg of calcium citrate and 2,000 mg of lactogluconate-carbonate.
As for vitamin D, of the nearly 40 studies that have been published involving both calcium and vitamin D combined, roughly half showed fracture reduction and half demonstrated no benefit.
Unless there is a clear benefit from something, we are unwilling to accept a risk. Although the risk of heart attack may seem small in absolute numbers, if tens of millions of women are swallowing large doses of calcium, the number of people who may be vulnerable is actually quite substantial.
We encourage visitors to actually read the BMJ article. It is free and very comprehensive. It is also understandable.
On our next radio show, we will discuss the pros and cons of calcium supplements with Amy Lanou, PhD. The following week we will hear from Michael Castleman, author of Building Bone Vitality and Water Willett, MD, DrPH, Chair of Nutrition at Harvard School of Public Health. You may wish to subscribe to our free podcast so you won’t miss these exciting interviews.

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  1. jds
    Reply

    As a therapist I spend many hours each day with clients who share lots of health concerns with me. Many are older women and almost every one either has osteoporosis, osteopenia or is worried about getting it. Many are on medicines to “prevent” osteoporosis. They also take calcium/Vit. D supplements since they have usually been tested for and found wanting in Vitamin D3. It seems odd that so many of us (myself included) are “deficient” in this vitamin, especially since we live in Florida and get plenty of sun exposure.
    The entire subject is very confusing. One has to wonder if the “goal post” has been moved, so to speak. My doctor prescribed 50,000 units once a week of Vit. D3. After a few weeks of this, I developed the most amazing itchiness all over my body. I finally figured, after reading the label of “adverse effects”, that it was from the Vit. D.
    My question is, how can I be so deficient and if D is so good for me, why did I develop this adverse reaction and further, what other systems in my body are now out of balance? This is a huge area of concern among women. It would be great if you could shed some light on this. Thank you.

  2. nf
    Reply

    This information is very helpful. As a vegetarian, I’d like to know if I need 2 servings of milk or yogurt to get adequate calcium and also phosphorus? I have osteoporosis and was taking a calcium-phosphorus supplement in addition to 1000 iu of D3.
    It would be great if your guests on Saturday could comment on this.
    Thank you.
    PEOPLE’S PHARMACY RESPONSE: YOU’LL FIND A LOT OF INFO IN THE BOOK, BUILDING BONE VITALITY. YOUR LIBRARY PROBABLY HAS A COPY.

  3. C R
    Reply

    I believe that the role of Vit D and other minerals is critical to the efficacy of calcium. I took Fosamax for 4 years, but did not improve my bone scores till my D levels were seen as low and additional D3 was recommended. I also refer you to the work of Dr. Charles Pak and his mineral metabolism research for University of Texas Southwestern Med School.
    He and those who worked with and after him found calcium to require d, magnesium, boron and other things to be properly utilized. Any review of research on calcium alone is not as helpful as it might be.

  4. J. David Auner
    Reply

    My patients were told almost ten years ago to stop elemental calcium whether in pills or added to foods. I had to look for 5 minutes on Friday to find a cheese slice that did not have calcium added and children’s cereals are worse.
    Heart attacks, worsening asthma, muscle cramps, arrhythmias, migraines, GI problems and others are probably related to poor absorption of divalent cations for 16 hours after calcium is ingested. Who is making the most money from this mess?

  5. Greg Pharmacy Student
    Reply

    Well done. Great summary and response. Medicine is complex. The unknown risks of drugs are not worth a the benefit, if the benefit is not proven. We should all look at drugs as though they are too good to be true.
    We must stick to what we ALL know we should be doing: eating a balanced diet and exercising regularly.

  6. KM
    Reply

    Just as the biochemistry of energy formation (The Krebs Cycle) is well-established, so too is the biochemistry of bone formation. A protein, osteocalcin, is needed to bind calcium in bones and vitamin D is required to synthesize this protein. However, vitamin K2 is needed to activate osteocalcin to enable it to carry out its job. In short, vitamin K2 keeps calcium in bones and out of the arteries where it can cause harm. To anyone who understands this, the BMJ article is not in the least bit surprising in its findings.
    All 23 nutrients required for healthy bone formation can be obtained from a healthy diet, so I’m not pushing supplementation. But an opportunity to use this study to educate the public about healthy bone maintenance has been lost owing to our obsession with single nutrient studies. The authors state: “The vascular effects of calcium supplements, especially without vitamin D, should be studied further.” Translation: “send more money for more studies” I was very disappointed with today’s show.

  7. LRR
    Reply

    Thank you for this information about calcium supplements. I have been taking 1000mg calcium supplement daily for years. Almost a year ago, September 2009 I had what my doctor called a mild heart attack, I failed a stress test, which led to a cath procedure which was clear, I remember the doctor saying it could possibly be from calcification rupturing or in some way blocking the micro vessels around my heart, he was baffled and so am I because the month before I had a health screening that indicated I was at very, very low risk of heart attack, low blood pressure, excellent total cholesterol, ldl and hdl numbers, slim, eat right, exercise.
    Why did I have this heart episode? I’m going to check out the BMJ article and make a copy for my doctor. Thank you again for providing information outside of the commercial norm.

  8. Barbara W.
    Reply

    I am interested in reading the BMJ article
    I am one of those thousands of women who took Fosomax faithfully for 10 years and
    BROKE MY FEMUR LAST NOVEMBER.
    I’m 86 and would like NOT to break anything else!
    Thank you for all you do! I listen faithfully and read the
    weekly email.
    Best
    Barbara
    PEOPLE’S PHARMACY RESPONSE: PASTE THIS LINK INTO YOUR BROWSER TO READ IT:
    http://www.bmj.com/content/341/bmj.c3691.full

  9. Dallee
    Reply

    As I noted in relation to the original post, the data indicated that there was NO additional risk if the calcium supplement was about 600 or below.
    The article failed to recognize this limitation.

  10. cpmt
    Reply

    In my opinion (only my opinion) in the Mediterranean countries, and I refer more to Spain, people don’t take much calcium suplements, and their sources of calcium came more from the type of food they eat, like many dishes are made with almonds etc. I see more people with bone problems and broken bones in this country. Doctors only prescribe calcium in specific cases when it is really necessary because of an illness.

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