Why People Use Coral Calcium for Better Health

coral reef
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Coral calcium is a form of calcium derived from coral reefs. Coral, which is made up of tiny animals related to jellyfish and sea anemones, forms a hard protective skeleton of calcium carbonate. When coral dies, new generations of coral grow on top of the calcium carbonate remains, eventually forming a coral reef.​

Much of the hype around coral calcium stems from the fact that coral calcium is harvested from coral in Okinawa, Japan. Okinawans are thought to have the longest life expectancy in the world and have low rates of heart disease and cancer. Marketers of coral calcium attribute it to their drinking water containing coral calcium. Researchers involved with the Okinawa Centenarian Study, however, debunk this claim, saying that hard water (water high in minerals such as calcium and magnesium) may increase calcium intake, but Okinawans still consume less calcium than people in Western countries.


Despite claims made by marketers, there is no evidence that coral calcium is superior to any other form of calcium. Coral calcium is calcium carbonate, the most common type of calcium on the market. Coral calcium isn't believed to be chemically different from other calcium carbonate products.

Although coral calcium contains small amounts of trace elements, such as manganese, there is no evidence supporting the potential benefits of the trace minerals.


People with shellfish allergies may develop allergic reactions after ingesting coral calcium supplements.

Also, not all of the trace elements found in coral calcium, such as cadmium, uranium, and mercury, are considered desirable or safe.

There are concerns that coral calcium, like other natural calcium carbonate sources oyster shell, dolomite, and bone meal, may contain lead.

It's important to keep in mind that supplements haven't been tested for safety and dietary supplements are largely unregulated. In some cases, the product may deliver doses that differ from the specified amount for each herb. In other cases, the product may be contaminated with other substances such as metals. Also, the safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has not been established. 

Using Coral Calcium for Health

Due to the limited research, it's too soon to recommend coral calcium for any health purpose. It's also important to note that self-treating a condition and avoiding or delaying standard care may have serious consequences. If you're considering using coral calcium, make sure to consult your physician first.

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Article Sources

  • "Consumer Advisory: Coral Calcium" NCCAM, National Institutes of Health. November 2004.

  • "Coral calcium: Safe for people with shellfish allergies?" Mayo Clinic Website. 24 Feb 2005.

  • "Coral Calcium" Claims Debunked. ConsumerAffairs.com. 10 Feb 2003.

  • "Marketers of Coral Calcium Product Are Prohibited from Making Disease Treatment and Cure Claims in Advertising" Federal Trade Commission. 22 Jan 2004.

  • "Okinawa Centenarian Study Position Statement on Coral Calcium" Okinawa Centenarian Study. 7 Jan 2003.