Medicine & Research

The Bare Facts About Coral Calcium

By MSF Staff and reviewed by the MSF Medical Advisory Board
Advertisers and infomercials claim that coral calcium can strengthen bones, promote weight-loss, and potentially cure over 200 diseases. And guess what? Consumers are buying it. According to SPINS, a San Francisco-based market research firm, within the past year, coral calcium has evolved into a $6.5 million dollar business.
Coral calcium sales soared as consumers learned of the exceptional health and longevity of people living on the Japanese Islands of Okinawa, where drinking water is rich in calcium derived from the surrounding coral reefs.
Two books, The Calcium Factor: The Scientific Secret of Health and Youth, and Death by Diet, both by Robert R. Barefoot, grew in popularity, promoting coral calcium as a natural way to maintain health and conquer degenerative diseases. Low pH levels in the body are disease culprits, the author maintains, and coral calcium can raise pH, thus preventing many diseases that are so prevalent in our culture.
Coral calcium, sometimes marketed as calcite or aragonite, is touted as having superior absorption. Other websites extol coral calcium's magical 2:1 ratio, which refers to its composition of 20 percent calcium and 10 percent magnesium.
The truth
Studies indicate that Okinawans probably owe their health and longevity to their diet, which is rich in vegetables, grains and fish, an active lifestyle, and strong familial ties throughout their lives. Low levels of pollution could also play a role.
As Barefoot, sometimes referred to as Dr. Barefoot or Dr. Robert Barefoot, Ph.D., avidly promotes coral calcium, he fails to mention that all calcium supplements can raise pH levels, not just coral calcium. Therefore, coral calcium is no different than any other type of calcium supplement in this regard. In addition, Barefoot is not a medical doctor and has not earned a Ph.D.
As for coral calcium's superior absorption, there is no reliable evidence proving that coral calcium is any more readily absorbed than calcium carbonate.
Some experts do believe a 2:1 ratio of calcium to magnesium is ideal, but this issue remains a controversial one. Beliefs differ on how much magnesium is optimal in calcium or whether there should be any magnesium in calcium supplements at all.
According to Gayle Nicholas Scott, Pharm.D., there is no scientific evidence that coral calcium can affect the body's pH, or that it is absorbed any better than other calcium supplements. It is also questionable whether magnesium content offers any additional health benefits. Many academic experts, mainstream and alternative medical practitioners, and even dietary supplement representatives agree with Scott's conclusions.
Others have expressed concern that coral calcium could trigger hives, breathing difficulties or swelling in those allergic to shellfish, as coral reefs often house such organisms.
"Coral calcium is not likely to offer better overall 'calcium-health' benefits than other forms of calcium," writes Takuo Fujita, M.D., founder of Japan's Calcium Research Institute, and past president of Japan's Osteoporosis Foundation. "Coral calcium is a supplement of reasonable quality. Other calciums have demonstrated better activity."
"Calcium is calcium," says Ellen Guthrie, Pharm.D. "But the body must have adequate vitamin D in order to absorb it. So, if you are taking calcium, make sure that you are getting an adequate amount of vitamin D. Many over-the-counter calcium products have vitamin D added. Another alternative is to take a multivitamin."
(Last reviewed 7/2009)