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Could too much calcium cause heart disease?

February 28, 2020
  • By Harvard Health Publishing Staff, Harvard Health

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Harvard Health Publishing Staff, Harvard Health

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December 9, 2011

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

Luis de Souza
December 4, 2011

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

November 18, 2011

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


Raju Ahamad
October 13, 2011

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

October 6, 2011

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

CA Bingham
September 26, 2011

Spinach is NOT good for Osteoporosis:

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.

September 21, 2011

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! 😀
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.

thomas thomas
September 17, 2011

I really appreciate your blog, thanks for giving us the awareness,don’t take too much calcium to avoid heart problem
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Ray Foucher
July 21, 2011

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

Ray Foucher
July 21, 2011

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.
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Jeff Davis
July 21, 2011

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.

What is zija
July 2, 2011

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.

Phoenix Pilates
June 8, 2011

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,

Emi Miller
April 3, 2011

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]

kirsten Plotkin
March 4, 2011

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

Nick Pokoluk
March 1, 2011

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.

February 23, 2011

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

February 8, 2011

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.
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Event Planning
January 26, 2011


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.

Keval Gajjar
January 25, 2011

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.

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Randell allen
January 18, 2011

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
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November 18, 2010

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!

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November 1, 2010

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.

October 27, 2010

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.

Beachbody Coach
October 4, 2010

Great looking site and great content. Keep it coming.

Allen Potas
October 4, 2010

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:


Mike Bundrant
September 19, 2010

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

Clint @ Crude Fitness
September 8, 2010

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.

Colon Cancer Prognosis
September 5, 2010

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.

June 30, 2011

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.

October 3, 2011

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.
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Kathi Casey
September 3, 2010

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

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