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David Baxter PhD

Late Founder
Diet Supplements and Safety: Some Disquieting Data
January 16, 2007
By DAN HURLEY, New York Times

In October 1993, during a Senate hearing on a bill to regulate herbs, vitamins and other dietary supplements on the presumption that they were safe, Senator Orrin G. Hatch, Republican of Utah, spoke up in their defense. Herbal remedies “have been on the market for centuries,” he said, adding: “In fact, most of these have been on the market for 4,000 years, and the real issue is risk. And there is not much risk in any of these products.”

That benign view was written into the bill when it was passed by both houses the following year. While the law, the Dietary Supplement Health and Education Act of 1994, forbade manufacturers to claim that their products “treat, cure or prevent” any disease, it allowed them to make vaguer claims based on a standard that did not require them to do any testing. And it stated that “dietary supplements are safe within a broad range of intake, and safety problems with the supplements are relatively rare.”

But hiding in plain sight, then as now, a national database was steadily accumulating strong evidence that some supplements carry risks of injury and death, and that children may be particularly vulnerable.

Since 1983, the American Association of Poison Control Centers has kept statistics on reports of poisonings for every type of substance, including dietary supplements. That first year, there were 14,006 reports related to the use of vitamins, minerals, essential oils — which are not classified as a dietary supplement but are widely sold in supplement stores for a variety of uses — and homeopathic remedies. Herbs were not categorized that year, because they were rarely used then.

By 2005, the number had grown ninefold: 125,595 incidents were reported related to vitamins, minerals, essential oils, herbs and other supplements. In all, over the 23-year span, the association — a national organization of state and local poison centers — has received more than 1.6 million reports of adverse reactions to such products, including 251,799 that were serious enough to require hospitalization. From 1983 to 2004 there were 230 reported deaths from supplements, with the yearly numbers rising from 4 in 1994, the year the supplement bill passed, to a record 27 in 2005.

The number of deaths may be far higher. In April 2004, the Food and Drug Administration said it had received 260 reports of deaths associated with herbs and other nonvitamin, nonmineral supplements since 1989. But an unpublished study prepared in 2000 for the agency by Dr. Alexander M. Walker, then the chairman of epidemiology at the Harvard School of Public Health, concluded: “A best estimate is that less than 1 percent of serious adverse events caused by dietary supplements is reported to the F.D.A. The true proportion may well be smaller by an order of magnitude or more.”

The supplements linked to the most reactions in 2005, according to the poison control centers, were ordinary vitamins, accounting for nearly half of all the reports received that year, 62,446, including 1 death. Minerals were linked to about half as many total reports, 32,098, but that number included 13 deaths. Herbs and other specialty products accounted for still fewer total reports, 23,769, but 13 deaths. Essential oils were linked to 7,282 reports and no deaths.

Among herbs and other specialty products, melatonin and homeopathic products — prepared from minuscule amounts of substances as diverse as salt and snake venom — had the most reports of reactions in 2005. The poison centers received 2,001 reports of reactions to melatonin, marketed as a sleep aid, including 535 hospitalizations and 4 deaths. Homeopathic products, often marketed as being safe because the doses are very low, were linked to 7,049 reactions, including 564 hospitalizations and 2 deaths.

But most other types of herbs and specialty supplements also appear in the annual report. In 2005, the poison centers received 203 reports of adverse reactions to St. John’s wort, including 79 hospitalizations and 1 death. Glucosamine, with or without chondroitin, was linked to 813 adverse reactions, including 108 hospitalizations and 1 death. Echinacea was linked to 483 adverse reactions, including 55 hospitalizations, 1 of them considered life-threatening. Saw palmetto was not listed on the report.

Injuries to children under 6 account for nearly three-quarters of all the reports of adverse reactions to dietary supplements, according to the poison centers. In 2005, the most recent year for which figures are available, 48,604 children suffered reactions to vitamins alone, the ninth-largest category of substances associated with reactions in that age group.

Major medical groups and government agencies do not generally recommend vitamin or mineral supplements for children who are otherwise healthy. But an analysis of the National Maternal and Infant Health Survey, published in the journal Pediatrics in 1997, found that 54 percent of parents of preschool children gave them a vitamin or mineral supplement at least three days a week.

Advocates of the products correctly point out that the poison centers’ figures do not prove a causal link between a product and a reaction and that, in any case, far more people are injured and killed by drugs. Painkillers alone were associated with 283,253 adverse reactions in 2005, according to the poison centers, more than twice as many as with supplements. But only 3.5 percent of those reactions occurred when people took the prescribed amount of painkiller; most were from overdoses, either accidental or intentional. The same was true of asthma drugs (3.6 percent of reactions were associated with the prescribed dose) and cough and cold drugs (3.1 percent).

While reactions to vitamins, minerals and essential oils occurred at similarly low levels when people took the recommended amounts, adverse reactions linked to the recommended levels of herbs, homeopathic products and other dietary supplements accounted for 10.3 percent of all reactions to those products reported to the poison centers — about three times the level seen for most drugs.

Drugs marketed in the United States go through a rigorous F.D.A. approval process to prove that they are effective for a particular indication, with the potential risks balanced against the benefits. While the approval process has come under attack in recent years as unduly favorable to drug companies, it remains among the toughest in the world.

There is no comparable requirement for supplements. Even so, hundreds of millions of tax dollars have been spent since the early 1990s on hundreds of studies to test the possible benefits of supplements. The National Center for Complementary and Alternative Medicine, established by Congress in 1991 to “investigate and validate unconventional medical practices,” has a 2007 budget of more than $120 million.

Since April 2002, five large randomized trials financed by the center have found no significant benefit for St. John’s wort against major depression, echinacea against the common cold, saw palmetto for enlarged prostate, the combination of glucosamine and chondroitin for arthritis, or black cohosh and other herbs for the hot flashes associated with menopause.

A new source of data on adverse reactions to dietary supplements will soon become available: in December, Congress passed a measure requiring the manufacturers of dietary supplements and over-the-counter drugs to inform the F.D.A. whenever consumers call them with reports of serious adverse events. The bill was signed by President Bush the day after Christmas. It is a welcome acknowledgment that “natural” does not always mean “safe.”

Dan Hurley is the author of the new book, Natural Causes: Death, Lies and Politics in America’s Vitamin and Herbal Supplement Industry (Broadway Books), from which this essay is adapted.
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