Tuesday, May 20, 2003

If you believe the recent flood of Internet ads, infomercials and health-food-store promotions for coral calcium -- and many apparently do -- this dietary supplement is not just the best way to ensure strong bones. It is also a weight-loss aid and a potential fix for more than 200 illnesses, including heart disease, diabetes, Alzheimer's, arthritis and cancer.

Dozens of U.S. and Canadian sellers of the product base their claims on what they say are the long and healthy lives led by people on the Japanese islands of Okinawa, where drinking water contains large amounts of calcium derived from the surrounding coral reefs. Americans, say these marketers, can follow suit by buying pills that cost as much as $1 a day -- some 20 times the cost of basic calcium carbonate pills.

According to SPINS, a San Francisco-based market research firm, calcium derived from coral has grown into at least a $6.5 million business over the past year.

"Tens of millions of people are using it," claims Bob Barefoot, 59, of Wickenberg, Ariz., the most prominent U.S. marketer of coral calcium, which he sells under such names as Coral Calcium Supreme and Best Coral Calcium Supreme Plus. "Can they all be wrong?"

Quite possibly, according to a wide array of academic experts, mainstream and alternative medicine clinicians and even dietary supplement industry reps. They say there is no evidence to support many claims made about coral calcium: Several studies suggest Okinawans more likely owe their longevity to such factors as a diet rich in vegetables, grains and fish; an active lifestyle; and strong social networks for the elderly.

Some skeptics also voice concern that coral calcium could trigger dangerous reactions -- such as hives, breathing difficulties or swelling -- in people with allergies to shellfish because coral reefs are often home to such organisms. Paul Takahashi, a geriatrician at the Mayo Clinic, cautions such patients against taking the product. He also worries that the product -- like all dietary supplements, it is only lightly regulated by the Food and Drug Administration (FDA) -- may contain harmful amounts of heavy metals such as lead, mercury and cadmium, which over time could cause digestive problems, kidney damage, nerve disorders and muscle and joint pain.

"It's the hottest quack product in the last 50 years," says retired Allentown, Pa., psychiatrist Stephen Barrett, who posts blistering critiques of alternative medicine on his "Quackwatch" Web site. "I've never seen such intense promotion in my life."

The Council for Responsible Nutrition, a trade group representing about 65 dietary supplement makers and suppliers, sought federal action against Barefoot and other manufacturers making what it calls "egregious" claims. "The problem with coral calcium is [that] many of the claims are over the top, with no scientific validity," said John Hathcock, the group's vice president for scientific and international affairs.

Government regulators have also taken note. As far back as 1999, the FDA issued a warning letter to a coral calcium marketer for unfounded therapeutic claims on its product labels. No further enforcement action was taken, according to an agency spokeswoman.

Under federal law, dietary supplements are not required to go through the same pre-market testing as do drugs to show safety and efficacy, but manufacturers are supposed to supply accurate and truthful labeling. If the FDA finds a supplement to be unsafe, the agency can call for a voluntary recall or force products off the shelves.

Recently, the Federal Trade Commission (FTC), which regulates product advertising, has signaled interest in coral calcium sales tactics.

Coral calcium "is certainly an area that historically, priority-wise, we would be very interested in," said Rich Cleland, assistant director of the FTC's division of advertising practices. "It's a widely marketed product, and there are some very strong therapeutic claims being made by some marketers."

A Hunger for Calcium Coral calcium marketers and their critics agree on two points: Calcium plays an important role in the body, and Americans aren't getting enough of it. Some evidence from recent studies suggests that calcium, besides maintaining bone strength, may be good for the heart, help lower blood pressure and improve blood lipid levels. An American Cancer Society study published in February also found that calcium may modestly reduce the risk of colorectal cancer. Federally funded researchers are recruiting patients for a study on whether high-dose calcium supplementation -- 750 milligrams twice a day for two years -- improves the health of overweight adults.

Eating calcium-rich foods, such as milk, dairy products and leafy green vegetables, is the preferred way to get calcium, say many clinicians and researchers. But the May 2001 Wellness Letter published by the University of California, Berkeley, found that, instead of getting the daily 1,000 milligrams that experts recommend for men and premenopausal women (post-menopausal women need 1,200 to 1,500 milligrams), the typical American woman gets 625 milligrams and the typical man 865. Calcium supplement sales accounted for $775 million in 2001, according to the Nutrition Business Journal, making calcium the third-highest-selling dietary supplement category, behind multivitamins and combination herbal products.

Barefoot, who received a two-year diploma in chemical technology in 1967 from Canada's Northern Alberta Institute of Technology, says he "discovered" coral calcium in the medical literature in 1982 and introduced the product in the United States in 1997. Last year, after selling his products largely online, he began a TV campaign that he says has helped boost monthly sales from 200,000 to 5 million bottles. In his infomercial and books, including "The Calcium Factor: The Scientific Secret of Health and Youth," "Barefoot on Coral Calcium" and "Death by Diet," he promotes calcium as "the nutrient of the 21st century."

Experts, however, contest many of the claims made by him and fellow coral calcium marketers, including these:

Absorption

Barefoot claims the calcium in his product is more easily absorbed by the body, thanks to "70 trace nutrients and the perfect amount of magnesium." Coral calcium, he says, is "70-plus [percent] absorbable by the body," compared with what he claims is 1 percent for the calcium-containing antacid Tums.

Robert Heaney, a professor of medicine at the Creighton University School of Medicine in Omaha, isn't buying that without proof. Heaney, who helped revise government recommendations on calcium intake in 1997, said he has asked Barefoot for data, without success.

Heaney also dismisses as "utter nonsense" Barefoot's assertion that Tums is 1 percent absorbable. Disbelief is also the reaction of Adrianne Bendich, clinical director of calcium research at GlaxoSmithKline, the maker of Tums. Heaney, who has tested the absorption of calcium products in the body, says pure calcium carbonate is 30 to 35 percent absorbable -- no matter how it is sold.

After an initial phone conversation, Barefoot did not return follow-up calls made to relay critics' comments and seek his response.

Kurt Althof, product manager of Coral Inc., in Incline Village, Nev., which sells the bulk raw material for coral calcium products, similarly claims coral calcium is better absorbed than other calcium supplements. He concedes, however, that he has no data to support this claim. Testimonals on coral calcium's benefits "have been so strong," he said, that "it almost doesn't need that science."

Calcium absorption is a less than straightforward matter

David Roll, director of dietary supplements for the Rockville-based U.S. Pharmacopeia, which sets voluntary quality standards for dietary supplements, explains that a tablet of 1,500 milligrams of calcium carbonate contains about 600 milligrams of calcium (40 percent of the total) that is available to be absorbed by the body -- of which perhaps 200 milligrams would actually be absorbed. The recommended daily intake of 1,000 milligrams of calcium, he says, is the amount experts say you should ingest, not how much would actually be absorbed.

Indeed, there's a limit to how much calcium can be absorbed at one time. John Swartzberg, clinical professor of medicine at Berkeley's School of Public Health and editor of the Wellness Letter, puts that limit at about 500 milligrams of calcium carbonate; some experts set it slightly higher. For this reason, experts recommend spreading calcium doses out over the course of the day.

Under a standard that became effective in 1995, Roll said, calcium carbonate products bearing labels of the U.S. Pharmacopeia (USP) must dissolve within 30 minutes, and dissolution is needed for absorption to occur. "No coral calcium products have the USP label as far as we know," he added. The Mayo Clinic's Takahashi said he recommends calcium carbonate for most of his patients because it is both effective for maintaining bone health and cheap. For those who find calcium supplements constipating, he recommends somewhat costlier calcium citrate supplements, which may be absorbed a bit more easily, meaning people may not not need to take as much. Incidentally, vitamin D aids calcium absorption; magnesium doesn't; "that's been thoroughly tested" by researchers, Heaney said.

Blood acidity

Barefoot and other coral calcium marketers claim that their products work by neutralizing the bloodstream's acidity, making it slightly alkaline, which helps to revitalize cells and promote health.

"That's absolutely bogus," says Swartzberg. He explains that the pH of the bloodstream is tightly controlled by the body and kept within a range of 7.38 to 7.42. He says there is no evidence that coral calcium can change the blood's pH or that such a change would be healthier. Indeed, he says, cells can't work optimally if the body is too alkaline or too acidic.

Product contents and pricing

Barefoot say his product is worth the $17 to $20 per bottle for which it sells online because it contains "marine coral," which sells for $44 per kilo. He said large retailers are able to market coral calcium for about $6 a bottle because they are "only buying dirt," using an inferior "rock coral" that sells for $1 a kilo.

That distinction is lost on Brent Bauer, chairman of the Mayo Clinic's complementary and integrative medicine program. He suspects that coral calcium products contain the same inexpensive calcium carbonate found in regular supplements, with "chunks of limestone, sandstone and debris that doesn't do anything."

Because dietary supplements are so lightly regulated in the United States, there is no independent testing of product contents and no way for consumers to know if they're getting what the seller says they are -- assuming those contents had therapeutic value.

Science

Barefoot cited a few recent Japanese studies that he said showed coral calcium's benefits. But Swartzberg and others said the studies were very small (one, cited widely on coral calcium Web sites, involved 12 people), poorly designed and not controlled. The Wellness Letter dismissed coral calcium in its February issue, saying promotional statements were based on "zero science."

"Everything we write about tends to be evidence-based," said Swartzberg. "No matter how hard we tried to keep an open mind on coral calcium, we could see no redeeming feature."

Judy Packer-Tursman is a Washington area journalist who writes frequently about alternative medicine.

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