Difference Between Calcium Citrate and Calcium Carbonate

Calcium is required for the human body to function at its full potential. Calcium is found in abundance in human bones and teeth. The role of calcium does not end here; we need enough calcium to structure the muscles and execute muscle movement, and the nerves require calcium to function properly. As we get older, we can’t keep up with the amount of calcium our bones need, resulting in a deficiency. As a result, we’ll be talking about two calcium supplements on the market: calcium citrate and calcium carbonate.


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Calcium Citrate vs Calcium Carbonate

The difference between Calcium Citrate and Calcium Carbonate is that their chemical formulas are different. Calcium Citrate is a calcium salt of citric acid, whereas Calcium Carbonate is a carbonate salt. They both are calcium salts with different anions, citrate, and carbonate. We’ll also look at their different functions as a micronutrient supplement.

Calcium Citrate vs Calcium Carbonate

The calcium salt of citric acid is calcium citrate. It is translucent and has a crystalline structure. It’s a clear powdery organic compound. It can be found in natural sources such as limestones or in citrus foods that contain citric acid, and it can also be created in a laboratory. Calcium Citrate is a calcium source that can be taken as a supplement and absorbs faster than calcium carbonate.

Calcium carbonate is a calcium salt that is formed when positive (cation) calcium reacts with negative (anion) carbonate. The salt oxidizes to calcium oxide and releases carbon dioxide at higher temperatures. It has a white powdery appearance and comes in the form of crystals. In contrast to Calcium Citrate, the rate of absorption of Calcium Carbonate in the body is lesser.

Comparison Table

Parameters of comparisonCalcium CitrateCalcium Carbonate
Chemical formula Ca3(C6H507)2CaCO3
Molecular weight 498.46 g/mol100.0869 g/mol
Calcium content21 percent (approx)40 percent (approx)
Absorption The absorption rate is more than twenty percent more than CaCO3.The absorption rate is lower.
Application  Calcium Citrate helps in softening hard water.Calcium carbonate raises the calcium concentration in water, resulting in hard water.

What is Calcium Citrate?

Calcium Citrate is an organic compound with a white crystalline or powdery texture that can be identified. It has the molecular formula Ca3(C6H507)2 and a molecular weight of 498.46 g/mol. The use of Calcium Citrate as a micronutrient supplement is discussed here. Calcium is an important micronutrient that is found in human bones, teeth, muscles, and nerves. And a lack of calcium in the body can have a variety of consequences. Calcium citrate can be taken as a supplement to prevent calcium deficiency, which can otherwise lead to serious consequences. It’s widely available in drugstores and has been compared to calcium carbonate; let’s see what the differences are.

Calcium citrate has a higher absorbance in the human body than calcium carbonate, according to a Harvard study. This is also because, as an organic compound, it dissolves in the body even without water. Aside from that, it has antacid properties and is used in industry for the chemical reaction that converts it to quicklime. Calcium citrate has a higher molecular weight than calcium carbonate. In terms of chemical properties, it is sour in acid, as any acid would be. Because of the citrate ion‘s ability to chelate, it can turn hard water into soft water.

calcium citrate

What is Calcium Carbonate?

Calcium carbonate has the chemical formula CaCO3 and is a calcium salt. It is used as a supplement to control calcium deficiency in the body. We need enough calcium in our bodies to maintain strong bones and teeth, as well as healthy muscles and nerves. We may experience difficulties if our bodies are unable to support the amount of oxygen required by our bodies. Carbon, calcium, and oxygen are the three elements that makeup calcium carbonate. It occurs naturally in rocks, primarily limestone. Its molecular weight per mole is 100.09 grams per mole. It is distinguished by its translucent color and lack of odor. It has a flaky or powdery texture, and it can also be crystalline.

Calcium carbonate, unlike calcium citrate, is slowly absorbed and has a lower bioavailability. Though calcium carbonate has a higher calcium content. Calcium carbonate has a calcium content of about 20% to 21%, whereas calcium carbonate has a calcium content of 40%. Furthermore, this is one of the factors that contribute to the hardening of water. Also, when it comes to availability, it is one of the most widely available chemical sediments. Compared to calcium citrate, calcium carbonate is less expensive. Calcium carbonate undergoes further oxidation, resulting in calcium oxide and carbon dioxide.

calcium carbonate

Main Differences Between Calcium Citrate and Calcium Carbonate

  1. Calcium citrate has the molecular formula Ca3(C6H507)2 and calcium carbonate has the molecular formula CaCO3.
  2. Calcium citrate has a molecular weight of 498.46 grams per mole, while calcium carbonate has a molecular weight of 100.09 grams per mole.
  3. Calcium citrate is 20% more bioavailable than calcium carbonate.
  4. Calcium citrate has a 20-21% calcium content, while calcium carbonate has a 40% calcium content.
  5. Hard water is softened by calcium citrate, whereas hard water is caused by calcium carbonate.
Difference Between Calcium Citrate and Calcium Carbonate


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