Many people believe that they need more calcium and decide to take calcium supplements. However, there are a lot of different calcium supplements out there. Which supplements are actually being absorbed by the body? Which types of calcium actually make their way into penetrating the cellular membrane?
Calcium comes in many different forms. Even with the other nutrients needed for its absorption, some forms are not as readily absorbed as others. Women often ask, “What about this or that type of calcium?” With all the different kinds of calcium supplements available, how do you choose, and how should you take them?
First off, not all calcium salts contain the same amount of elemental calcium. (Elemental calcium is the amount of calcium actually absorbed by the body.) For example, there is more elemental calcium in calcium carbonate than in calcium gluconate. However, your body may not be able to absorb it as well. Make sure the label of the calcium product you choose lists the amount of elemental calcium, as well as the total calcium. If the phrase “elemental calcium” is not listed, find another calcium supplement.
Absorption is another problem. Generally speaking, all types of calcium are absorbed more easily if taken with meals – no matter what form you choose.
Then, there can be an issue with price or ‘trendy’ forms. We thought we’d offer a little help.
Calcium Supplements – A Brief Guide to Common Types
1. Calcium Carbonate
This type of calcium supplement is the least expensive (cheapest) and most commonly used calcium supplement. Calcium carbonate is an alkaline-based compound found in rocks, limestone, shells of marine animals, pearls, eggshells and snails.
It holds one of the highest concentrations of elemental calcium (35-40%). However it is not high in bioavailability. (Bioavailability refers to the amount of calcium in the supplement that can be absorbed and assimilated by the digestive system. This makes it actually usable for cellular activity and health benefits.)
It requires the production of extra stomach acid to be absorbed so is absorbed best when taken with meals. Breakfast is the best time to take calcium carbonate because the body absorbs it best when taken with a low iron meal. (Too much calcium carbonate may also cause constipation.)
2. *Calcium Citrate
We prefer calcium citrate because it is well absorbed and tolerated by most people. It has been proven to help bone density and the citrate may help to prevent kidney stones.
Calcium citrate may also be a better calcium supplement choice for people with reduced levels of stomach acids. This is especially true with more concerned older people with bone problems. Calcium citrate is different than calcium carbonate because it has an acidic base. It does not require as much hydrochloric acid (HCl) in the stomach to be absorbed, requiring less production of natural stomach acids. This allows it to be better absorbed than the carbonate form, makes calcium citrate easily absorbed and less likely to cause abdominal discomfort
It does have less elemental calcium concentration and bioavailability. However, with the nutrients we recommended, it absorbs well and doesn’t have to be taken with meals! Calcium citrate works equally as well when taken with or without food. Thus, calcium citrate is very readily absorbable and a good choice for people with low stomach acid.
3. Oyster Shell, Bone Meal & Dolomite Calcium
These seem like they are a more natural form of calcium and, thus, better for you. However, oyster shell calcium is very difficult to find good quality control. They are often found to show unacceptable levels of heavy metals, including lead toxins. Minimizing lead intake is important for pregnant and nursing women, and children.
Currently, calcium supplements are not tested by a regulatory agency for lead content before they are placed on the market. It is up to the manufacturer to assure that the lead content of their calcium supplement meets the FDA standards.
In general, then, these “natural forms” of calcium should be avoided.
4. Calcium Gluconate
Calcium Phosphate, Calcium Lactate, and Calcium Gluconate are forms of calcium with a lot of “bioavailability” promotion in ads. Unfortunately, they have very low levels of actual calcium in each supplement tablet. Therefore it is necessary to take a large number of tablets to consume an adequate amount of calcium every day to reach normal calcium requirements (as well as a higher price) and the bioavailability is still not certain.
5. Calcium Lactate
This is the form of calcium found in foods such as aged cheese and baking powder. This form is a commonly used antacid and is added to fruits to keep them firm and extend shelf life. It has a medium bioavailability in the body because it can be absorbed at various pHs. As above, Calcium Phosphate, Calcium Lactate, and Calcium Gluconate have very small percentages of elemental calcium in each supplement tablet. Therefore it is necessary to take a large number of tablets to consume an adequate amount of calcium every day.
6. Calcium Phosphate
This is the main form of calcium coming from cow’s milk. Tooth enamel and bones are very high in calcium phosphate (although supplemental forms have not shown to be readily bioavailable). This type of calcium supplement is the least likely to cause constipation. As above, Calcium Phosphate, Calcium Lactate, and Calcium Gluconate have very small percentages of elemental calcium in each supplement tablet. Therefore it is necessary to take a large number of tablets to consume an adequate amount of calcium every day.
7. Calcium Citrate Malate
This is a water-soluble form of calcium. It is created through mixing the calcium salt found in citric acid with malic acid. This combination has higher levels of bioavailability than the other forms listed above because it is water-soluble. It also shows some evidence of being dissolved into cell membranes. Not a bad choice if money is a problem.
8. Calcium Orotate
This is a very effective form of calcium supplement, created through the use of the mineral salts of orotic acid. Calcium orotates are found in small amounts in all living beings. It is a primary mineral for the creation of bones and teeth, and fosters cellular communications.
Both plants and animals use orotates to create DNA and RNA. Extensive scientific research done by by Hans A. Nieper, M.D. has found that orotates can penetrate cell membranes, enabling the effective delivery of the calcium ion to the inner-most layers of the cellular mitochondria and nucleus. However, with the nutrients added to the products we recommend, we can achieve better results for less money (it is expensive)! But then, the grandkids don’t need their college fund anyway.
9. Calcium ascorbate
This is generally not as easily absorbed as the citrate forms – especially if stomach HCl is low. However, they are absorbed quite readily when taken with food. There is really no good reason to get this over other alternatives.
10. MCHC Calcium
We are sometimes asked about microcrystalline hydroxyapatite (MCHC). It is an interesting calcium containing substance derived from animal bones that may have its merits. This is especially true for older people with very low-phosphorus diets, or those who don’t get enough meat or protein (which are not problems for the average American).
However, it is quite costly. Its amino acid content varies depending on how it’s processed, it does not contain magnesium, and there are actually few supportive studies on it. So, all in all, we do not think microcrystalline hydroxyapatite is “way superior” to other forms of calcium and perhaps the premium on it may be somewhat misplaced.