The Health Benefits of Coral Calcium

Coral calcium is a form of calcium derived from coral reefs that form over thousands of years. 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.​

coral calcium
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Much of the hype around coral calcium stems from the fact that the ingredient 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 these health benefits to the fact that Okinawans drink water containing coral calcium.

Researchers involved with the Okinawa Centenarian Study have debunked 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.

Health Benefits

People have used coral supplements to treat conditions including multiple sclerosis, cancer, heart disease, and other chronic health problems. But 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. In fact, health experts have reported that coral calcium contains the same ingredients as calcium carbonate products commonly found in grocery stores and pharmacies.

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

Independent, high-quality studies supporting coral calcium as a dietary supplement are limited and provided little evidence to support its use as a treatment for illness or to provide health benefits. However, one review of studies examining the anti-inflammatory properties, anti-cancer properties, bone repair, and neurological benefits of coral did find enough evidence to suggest that more research is warranted.

Dietary calcium—and potentially calcium supplements—may play a role in the treatment of certain conditions including bone loss, osteoporosis, colon cancer, heart disease, and hypertension. Investigators are still evaluating the extent of the benefits and whether or not supplements can be as effective as calcium consumed in food.

Possible Side Effects

Coral is sometimes used by surgeons to replace bone. It is likely safe when used for this benefit. However, there is not enough evidence to determine if coral calcium supplements are safe when consumed by mouth.

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.

Women who are pregnant or breastfeeding are advised to avoid coral calcium supplements.

It's important to keep in mind that dietary supplements are largely unregulated by the FDA. Although it is illegal to market a dietary supplement product as a treatment or cure for a specific disease or to alleviate the symptoms of a disease, supplement products are not tested for safety or effectiveness by the FDA.

In some cases, dietary supplements may deliver doses that differ from the amount indicated on the label. When choosing a supplement, it's best to look for products that have been certified by ConsumerLabs, The U.S. Pharmacopeial Convention, or NSF International. These organizations don't guarantee that a product is safe or effective, but they do provide a certain level of testing for quality. 

A Word From Verywell

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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