"If it's natural it must be reasonably safe." As noted earlier, dietary supplements-even many herbal products-are heavily processed extracts, synthetics, concentrates and fermentation products. However, even without industrial processing, to assume that a product originating from plants is therefore safe is just bad biology. "Natural products are not necessarily safer than conventional products," noted Tyler

The proof of Tyler's statement can be rapidly verified. Walk out the front door and consider eating the "natural" plants you see. Grass? (The celluose makes it indigestible) Oak leaves? Azalea bushes? A little longer journey will place you near more lethal hazards. Pick mushrooms in the woods at random and you are likely to get a deadly poison. Do you like almonds? Raw, wild almonds are loaded with lethal cyanide poison. "Of about 200,000 plant species, only a few thousand are eaten by humans, and just a few hundred of these have been more or less domesticated," noted Jared Diamond in his Pulitzer Prize-winning book, "Guns, Germs and Steel." Plants are chemical factories of great power and diversity and capable of manufacturing compounds for a wide variety of human uses: foods, dyes, medicines, paper, fabrics, poisons, glue, and construction materials to name only a few. Whether to make a useful medicine or valuable glue, the plant has to be studied, understood and tested.

"These products have a history of safe use, often for a century." A similar idea is behind the 1994 law that deregulated dietary supplements. It declared that any product then on the market, "had a history of use," and was therefore acceptable. What history teaches is that for thousands of years, foolish and ignorant humans consumed remarkably toxic compounds, believing they would improve their health.

For example, just sample the drugs-many of them natural-recommended a century ago in the 1899 version of the Merck Manual. How should an ulcer be treated? The Merck manual recommended creosote, turpentine oil, charcoal, mercury, arsenic, lead, cocaine, opium, and marijuana. Such toxic medical practices explain the popular rise of homeopathy--which involves giving infinitesimally small doses of "like" chemicals. Patients would indeed improve merely because the doses were so tiny that no harm was done, likely a better outcome that from the toxic treatments recommended in the 1899 Merck Manual. But this does not explain why so many people today still believe a history of safe use is a reasonable assurance of safety, or justify the increasing sales of homeopathic remedies in health stores.

"It has been used safely in China for 1,000 years." In fact, traditional Chinese medicines are frequently found to have toxic effects, especially as the products are grown elsewhere and used outside the traditional Chinese framework of care.

Last June the California Department of Health Services warned of taking An Shu Ling after it was linked to hepatitis. A month earlier it ordered the recall Hui Chun Tan, after a 2-year-old was hospitalized with seizures. It contained borneol, which causes nausea, vomiting, and liver damage. A medical report from Japan linked cases of hepatitis E to Chinese herbal medicines. This strain of hepatitis is endemic in China, but rarely seen in industrialized nations. Could herbal medicines be causing or contributing to a disease epidemic? Other Chinese herbal medicines linked to serious adverse events include Jin Bu Huan (hepatitis) Bajiaolian (impaired blood cells), and Syo-saiko-to (gallstones).