What Kind of Calcium is Best for Healthy Bones?

If you have osteopenia or osteoporosis, you may be taking a calcium supplement, but did you know that some calcium supplements are far better than others for healthy bones? Here are a few basic facts about calcium:

  • Calcium is an element, as is iron, hydrogen or oxygen. An element cannot be broken down into any other form, but when we take it as a nutritional supplement, it may be delivered to us in a variety of ways.
  • Most mineral supplements occur as compounds, such as magnesium citrate, or calcium carbonate, and each mineral may appear in different forms.
  • If your vitamin label says, Calcium (elemental) it is calcium carbonate.

Your vitamin label may read as something other than the above. Maybe it says “calcium citrate” or “calcium gluconate”,  “coral calcium” or “diacalcium malate”?   There are several types of calcium from which to choose, and the whole thing can get very confusing, especially if you are hoping to take the best calcium supplement for osteopenia or osteoporosis.

The Many Types of Calcium for Healthy Bones


Calcium Carbonate

According to the National Institutes of Health's Office of Dietary Supplements, calcium carbonate is the most widely used form of supplemental calcium. Quite simply, it is a combination of the element calcium combined with elemental carbon and elemental oxygen.  When our bodies digest calcium carbonate, the elemental calcium breaks away from the carbon and oxygen atoms.

So, when you see the words Calcium (elemental) as a supplement ingredient, it means you are getting calcium carbonate.  But not all labels list the source of the calcium carbonate; nor do they tell you how much calcium your body is absorbing. 

Calcium carbonate is made from rocks, through the extraction and processing of natural ores. It can also be made synthetically through chemical precipitation.

For every tablet that contains 1000 milligrams of calcium carbonate, only 40% of that total (400 mg) becomes available for absorption in your body. The other 60% is just carbon and oxygen. That means, if you need to take 1000 milligrams of calcium every day, you had better take 2.5 of those tablets to meet your requirements.

Calcium Citrate

Another widely available form of calcium supplement is calcium citrate. It is the calcium salt of citric acid, and it is made from citrus juice concentrates. It can also come directly from citrus fruits like orange, lime, lemon or grapefruit.

Calcium citrate is commonly prescribed by health care providers and is the main form of calcium in the popular supplement “Citrical”. Unlike Calcium Carbonate, Calcium Citrate provides only 20% of elemental calcium. Expect to take more tablets, and consequently, to pay for more for your calcium needs. But here’s the upside.

According to medical sources, calcium citrate is more easily absorbed into the bloodstream. Why? You can take it without food, whereas, calcium carbonate must be taken with food for adequate absorption. If you have a sensitive stomach, or you don’t want to wait for the next meal to take your vitamins, you may want to consider calcium citrate. Be aware, that although calcium citrate appears to be more gentle, according to intelihealth.com, some people still experience stomach upset. What's more, it may not be your best choice for reversing bone loss.

Calcium Gluconate

Calcium gluconate comes in tablet and powder form. You may also receive a calcium gluconate injection.  In addition to helping you treat or prevent a calcium deficiency, this supplement is used to reduce the level of phosphate or phosphorus in the body. Doctors prescribe calcium gluconate to patients who have both needs. According to Drugs.com, calcium gluconate can interfere with the effects of certain medications and other types of calcium and vitamin D supplements.

What about Coral Calcium?

Coral calcium is a form of calcium composed primarily of calcium carbonate. Widely advertised as being better than the rest, coral calcium is harvested from fossilized coral beds along coastlines. Grains are then ground into a fine powder, heat treated and combined with silicon dioxide (an anti-caking ingredient), rice flour, and magnesium stearate which acts as a lubricant.

Coral calcium has recently become a target for criticism because of all the hype and false information advertised by manufacturers. Environmental groups have also expressed concern regarding coral calcium.

Living coral reefs are endangered, so harvesting now takes place above-ground in limestone deposits that were once part of a coral reef, or from the beach or the ocean floor so as not to disturb the living coral reefs.  Some argue that harvesting the dead coral lying on the ocean floor disturbs the sediment, which harms living coral.

The CBS Business Library reports,

“Other issues haunt popular calcium supplements present and past. For example, unrefined calcium sources such as oyster shell, bone meal, and dolomite were once popular but have fallen out of favor due to high levels of toxic metals (such as lead).”

Tod Cooperman, M.D., president of ConsumerLab.com, said in a recent press release, “We have received many questions from consumers about coral calcium. Coral calcium is not inherently better or worse than other types of calcium. But it is sadly ironic that the most advertised brand also had the most lead.”

What is the Best Calcium to Take?

Calcium is also known to help strengthen your bones, but I learned that just taking a calcium supplement alone is not enough. You need to combine it with magnesium for proper absorption. I recommend taking a Calcium Magnesium Citrate supplement for building and maintaining healthy bones.


The bottom line is to read the labels and do the research.  If you want to have healthy bones to prevent or reverse osteoporosis, then you need to get into the truly advanced forms of calcium that prevent or reverse osteoporosis and osteopenia.

I also recommend choosing all natural supplements, without unnecessary fillers. Good old-fashioned vitamin and mineral supplements may no longer be good enough…just old-fashioned.

Remember, reputable companies are also upfront with their ingredients.

Hopefully this article has cleared up some confusion about what kind of calcium is on the market and which supplement is the best for maintaining and restoring healthy bones.

All information provided on this site, particularly any information relating to specific medical conditions, health care, preventive care, and healthy lifestyles, is presented for general informational purposes only. It should not be considered complete or exhaustive and does not cover all disorders or their treatment. It is not a substitute for the advice provided by your own physician or health care provider, and may not necessarily take your individual health situation into account.


    • Andrea T. H. W. on May 14, 2012 at 11:43 am
    • Reply

    Great post Hillary, I had to share it through Livefyre. Really detailed and well explained. Thumbs up. 🙂

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