Patrick J. Skerrett

Could too much calcium cause heart disease?

Don’t throw out those calcium supplements just yet.

Oh, the ruckus a single study can raise. A report about calcium and cardiovascular disease had people from San Diego to Caribou, Maine worriedly calling their doctors or throwing away the calcium supplements they were taking to keep their bones strong.

Here’s what prompted the concern: New Zealand researchers pooled the results of 11 randomized, controlled trials—the so-called gold standard of medical research—comparing the effects of calcium supplements and placebo on preventing osteoporosis or colon cancer. All the trials also had information on the volunteers’ cardiovascular health. As reported online in the BMJ, more of the volunteers taking calcium had heart attacks, stroke, or died suddenly than did those taking the placebo. Media reports duly noted a 30% increased risk of cardiovascular disease with calcium supplements, which sounds scary. Another way to put the findings: 5.8% of those taking calcium had a cardiovascular event, compared with 5.5% of those taking placebo.

This publication is just another piece of the calcium puzzle. It isn’t a practice changer. Some prior studies have shown that taking calcium supplements is linked to cardiovascular disease, others haven’t.

The connection between calcium and cardiovascular disease is plausible. Calcium deposits are part of artery-clogging plaque. They also contribute to stiffening of the arteries and interfere with the action of heart valves. But whether there is a direct connection between the amount of calcium in the bloodstream (calcium supplements increase blood calcium levels) and cardiovascular problems isn’t yet known.

An even bigger unanswered question is how much calcium the average person needs each day to keep bones strong and healthy. At one end of the spectrum, the World Health Organization says 400 to 500 milligrams (mg) of calcium a day are needed to prevent osteoporosis. At the other end, the official recommendation for Americans is 1,000 mg/day from ages 19 to 50 and 1,200 mg/day after that.

Given the uncertainty about the balance of benefits and risks of calcium supplements, it’s probably best not to rely just on this mineral to keep your bones strong and prevent bone-thinning osteoporosis. Other options include:

  • Weight-bearing exercise, like walking, running, tennis, and others, is one of the best things you can do for your bones.
  • Getting enough vitamin D, from sun and supplements, is also good for bones and overall health. (As with everything, don’t overdo it—no more than 10 to 15 minutes of sunshine without sunscreen, and/or 800 to 1,000 IU of a vitamin D supplement.)
  • Vitamin K from green leafy vegetables such as spinach, Swiss chard, and kale is also important for bone health.

A single study rarely changes health recommendations. This New Zealand study alone definitely shouldn’t change advice on calcium supplement. It should, though, nudge you to talk with your doctor about calcium, and do other things to protect your bones.

Comments:

  1. Mike

    I read about this study recently and I’m so glad I came across your article. I suffered a mild heart attack a few weeks ago and because of the study, I halved me usual 1000mg of calcium. Because of my osteoporosis I have been tempted to return to the full dose. I live a very healthy lifestyle. I haven’t smoked for 25 years, I don’t drink alcohol and I follow a low carbohydrate diet. Despite all that, I think, after reading your article that I should continue on the lower dose. Thank you for confirming I’m on the right track.
    Kirsten Plotkin

  2. Luis de Souza

    People get strong bones by exercising, is doesn’t matter how, but weigh lifting can be surely the best way to do it.

  3. Anonymous

    Thanks for this useful information..it’s best to get the necessary calcium through whole foods anyway.

    Great…

  4. Raju Ahamad

    Thank for your informative article. Its really so much needy.

  5. Anonymous

    Very thanks for this great information.Yoga is also good exercise options for keeping our bones healthy.

  6. CA Bingham

    Spinach is NOT good for Osteoporosis:

    http://www.osteopenia3.com/Diet-for-Osteopenia.html

    What foods interfere with the absorption of Calcium?
    Oxalates (such as spinach, sweet potatoes and beans) and Phytates (such as whole wheat bran, beans, nuts and soy isolates) interfere with the absorption of calcium. So, for example, eating a piece of hard cheese alone or in a salad may be fine but eating a cheese sandwich or cheese on beans could be problematic.

  7. Marvin

    Thank you for the balanced look at nutrition! I truly appreciate that the answers given here are more toward using the body for maintenance rather than relying on a pill. Eating kale is brilliant! :D
    One question I have, though, is what about the ‘type’ of calcium supplement, like a source from citrus vs diary? And what about each person dietary choices? It seems to me that, as you have said, one study cannot and should not change our health and nutrition habits.

  8. thomas thomas

    I really appreciate your blog, thanks for giving us the awareness,don’t take too much calcium to avoid heart problem
    [URL removed by moderator]

  9. Ray Foucher

    There is a lot of confusion about the causes of osteoporosis.

  10. Ray Foucher

    An understanding of the effect of calcium supplements on osteoporosis is somewhat complicated by the fact that calcium affects bone density in more than one way. Calcium is needed to make bone but in smaller amounts than most people believe. In third world countries with an average daily intake of less than the WHO’s 400-500 mg there is little osteoporosis. Yet in western countries where recommended intakes are 2-3 times that, osteoporosis is becoming epidemic. It is not from a shortage of calcium in the diet but from a diet too high in animal protein that results in leaching of calcium from the bones putting the subject in a negative calcium balance.
    The other effect is that calcium supplements, being very basic tend to neutralize some of this over acidity. But then that also reduces stomach acid which impairs food digestion.
    [URL removed by moderator]

  11. Jeff Davis

    Hi, I am glad you took the time to put people’s minds at ease after the release of the report from NZ. Your comparison of the two groups which showed that the placebo group showed little difference from the calcium taking group only goes to reinforce the idea that the press whips up stories to fill their pages.
    I was also interested to see you mention vitamin K as a supplement – I only ever thought of this as an aid to increasing coagulation in blood.

  12. What is zija

    I can’t imagine that any amount of vitamins could be bad. How often do you hear on the news some one dieing from a vitamin over dose? Never. I am concerned with the way that people and young doctors are taught about vitamins and nutrition these days.

  13. Phoenix Pilates

    This study doesn’t seem conclusive enough to warrant any changes to calcium supplementation. However, just as all nutrition advice has claimed, it’s best to get the necessary calcium through whole foods anyway.

    Plus as an avid fitness enthusiast, I have found strength training and other exercises like Pilates have helped me to maintain great bone health.

    In fact I proudly admit that at over 40 years of age, my bones are more dense than those at half my age. Thank God for genetics and a desire to stay healthy through exercise.

    Phoenix Pilates,
    Jolene

  14. Emi Miller

    KIND OF CALCIUM IN STUDIES AND ‘SIPPY DISEASE’ CAUSING DEATH
    HI ALL… Here and there!

    How about the kind of calcium in the studies? Carbonate, from shells, coral and the like appears to not be absorbed fully, and end up in the bloodstream… also in the Kidneys, causing stones… and this interesting find, the “Sippy Disease”… throws some more light on the body becoming too alkaline — from excessive calcium in the bloodstream … (find article on Wikipedia, with good sources noted) ~ Emi

    Excess calcium from supplements, fortified food and high-calcium diets, can cause the milk-alkali syndrome, which has serious toxicity and can be fatal. In 1915, Bertram Sippy introduced the “Sippy regimen” of hourly ingestion of milk and cream, and the gradual addition of eggs and cooked cereal, for 10 days, combined with alkaline powders, which provided symptomatic relief for peptic ulcer disease. Over the next several decades, the Sippy regimen resulted in renal failure, alkalosis, and hypercalcemia, mostly in men with peptic ulcer disease. These adverse effects were reversed when the regimen stopped, but it was fatal in some patients with protracted vomiting. Milk alkali syndrome declined in men after effective treatments for peptic ulcer disease arose. During the past 15 years, it has been reported in women taking calcium supplements above the recommended range of 1.2 to 1.5 g daily, for prevention and treatment of osteoporosis, and is exacerbated by dehydration. Calcium has been added to over-the-counter products, which contributes to inadvertent excessive intake. Excessive calcium intake can lead to hypercalcemia, complications of which include vomiting, abdominal pain and altered mental status.[11]
    http://en.wikipedia.org/wiki/Antacid

  15. kirsten Plotkin

    I read about this study recently and I’m so glad I came across your article. I suffered a mild heart attack a few weeks ago and because of the study, I halved me usual 1000mg of calcium. Because of my osteoporosis I have been tempted to return to the full dose. I live a very healthy lifestyle. I haven’t smoked for 25 years, I don’t drink alcohol and I follow a low carbohydrate diet. Despite all that, I think, after reading your article that I should continue on the lower dose. Thank you for confirming I’m on the right track.
    Kirsten Plotkin
    http://www.healthylifestyle-news.org

  16. Nick Pokoluk

    Yikes – I have GERD and eat Tums like candy. I do all else right and have bery good lipid panels < 150 TC, < 80 LDL and very low CRP but really have a lot of calcium carbonate and have for 40 years!!!! Wouldn't that be a kicker. Vegan, exercise, no smoking and done in by Tums.

  17. john

    Great post!!
    I’ve wondered if there are some disadvantages of consuming too much calcium, thanks for the answer.
    John.

  18. Pilates

    Pilates can be one of the best exercise options for keeping bones healthy and strong. Many of my clients are over 60 and Pilates classes are helping them to regain bone density, improve strength and flexibility. I do agree though that it is too early and not enough is yet known about calcium supplements for anyone to risk stopping them. Balance in all things, exercise, supplements, good diet and nutrition and always be aware of your stress levels.
    [URL removed by moderator]

  19. Event Planning

    Hi…

    Great Post and great content. I don’t know about disadvantages of too much Calcium but it is really helpful to strong bones and teeths specially for growing children.

  20. Keval Gajjar

    Yes thats absolutely correct that by practicing yoga and meditation anyone can cure their decease but it should be done under expert’s supervision, that can give very better result to the person who’s suffering from the decease.
    Thank you very much for sharing this useful article.

    [URL removed by moderator]

  21. Randell allen

    As a nutritionist and personal trainer, I amazed that despite the recommendations to lift weights, many women still shy away from weight bearing activities in fear bulking up. It’s nice to see a post directed at including weight training as a vital part of bone health. I would like to know if there were other factors involved in the calcium group and heart disease, correlation is not causation.

    Randell Allen
    [URL removed by moderator]

  22. Chris

    Besides eating healthy, there are many factors in how your body can handle amounts of calcium. We need to teach our kids at a young age safe and fun alternatives to living a healthy lifestyle. Alternative transportation is a step we can take to help our environment as well as health as a whole country. We have determined what our problems are and will continue to be unless we stand up and change. Many great people regardless of their lifestyles are opening their eyes to this. I myself ride around on electric bikes to do my fair share of preservation. You can help too. 30 minutes a day on a bike is fun and easy!

    Chris
    [URL removed by moderator]

  23. John

    Too much calcium is definitely dangerous for increasing a risk of heart disease. With out magnesium, vitamin D and certain trace minerals then the calcium can damage arteries.

  24. Leslie

    In addition to weight-bearing exercise, and getting enough vitamin D and vitamin K, another way to prevent osteoporosis in middle-age and older men, is to increase testosterone levels. Low testosterone has been shown to be directly linked to increased fracture rates and osteoporosis.

    Another benefit of increasing testosterone? Heart health. Many studies indicate that testosterone levels are directly related to increased incidence of heart disease and coronary artery disease — as well as type 2 diabetes, obesity, depression, metabolic disease and many of the other diseases of aging.
    Leslie

  25. Beachbody Coach

    Great looking site and great content. Keep it coming.

  26. Allen Potas

    The Institute of Medicine has a panel report on the reduction of bone loss (along with reduced incidence of kidney stones and blunting of sodium effect on hypertension) from a high potassium diet. The table on their recommended dietary allowance can be found at: http://iom.edu/Activities/Nutrition/SummaryDRIs/~/media/Files/Activity%20Files/Nutrition/DRIs/DRI_Electrolytes_Water.ashx

    Allen
    http://www.highpotassiumfoods.org/

  27. Mike Bundrant

    I just had my vitamin D level checked and I showed a score of 1,8 which is awful. Normal scores are between 75 and 100, according to my doctor. I am 42 years old and get plenty of sun here is Southern California. I have even made a practice of sunning for a little bit every day in the earlier morning hours – before 10 AM. At any rate, I was very surprised and now take a vitamin D supplement. My doc also said that any D supplement will work – we don’t need to buy overpriced D that claims better absorption.

    Thanks, Mike

  28. Clint @ Crude Fitness

    Nice post indeed. It’s great to see weight-bearing exercise being recommended regardless of gender. Bone density is something the ladies I talk to forget when deciding upon an exercise program — too concerned about becoming to big and muscle-bound.

  29. Colon Cancer Prognosis

    Basically, the building of good strong bones need a range of minerals and vitamins such as magnesium, vitamin D, omega-3 fatty acids, silicon, vitamin K, and of course calcium. So calcium is always the biggest component in any nutritional supplements for the bone.

    Calcium supplements must contain all these vitamins and minerals, because without these essential components, the calcium may not be absorbed in the bones where it is intended, and might end up in our blood vessels or our heart, where it causes harm. So long as these other nutrients are taken as well, many studies have shown that added calcium plays an important role in building and maintaining bone mass.

    • Sandra

      Thank you for the comment about additional supplementation needed for calcium to be absorbed into bones. K is the traffic cop that tells the calcium to be reaborbed into our bones and tissues. Frankly, I think there is way too much hype about Vitamin D – I think it is causing cardiovascular disease and high blood pressure. Vitamin D actually leaches calcium from our bones and tissues.

    • Joey

      If the calcium is enzymatically alive as in a food source. We benefit greatly. Is tough finding good vitamins because they are mostly synthetic and our bodies reject anything of this nature. Hence the discoloring of urine.
      Moringa is being studied as we speak by the Hopkins Hospital of Medicine, National Institute of Health and a hundred others. The calcium is just one of 94 vitamins provided is such a way that our bodies love us for taking it.
      There is more info in link. Thanks, great post.
      Joey
      [URL removed by moderator]

  30. Kathi Casey

    Nice to hear a rational, simple explanation for the bad press. Thanks, I will share this on my site.
    Yoga and Pilates are also good exercise options for keeping our bones healthy. I’ve personally seen women over 60 use my Pilates classes to gain back bone loss and improve their over-all strength.
    Kathi Casey