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Smart shopping takes on new meaning when it comes to herbal products. Herbs can both cause and cure illness, but labels on herbal products are often unreliable. So consumers must do careful research before stepping into the store.
Lax Labels
The U.S. Food and Drug Administration requires rigorous and expensive testing before a manufacturer can make any health claims for its products. Few herbal products have been tested in this way, so labels on herbal remedies usually don't tell you what illnesses they're used to treat.
By law, an herb's label must say how much each dose contains. But many such labels are inaccurate. In an unpublished 1999 study conducted by the Center for Dietary Supplement Research in Botanicals at the University of California, Los Angeles, four of nine panax ginseng products did not contain the percentage of the key ingredient ginsenoside that their labels claimed. The content ranged from 30% to over 266% of the stated amount.
The sad truth is that no agency keeps a particularly close eye on herbs. "The Food and Drug Administration does not have any mechanism to do surveillance or monitor these kinds of products," says William R. Obermeyer, PhD, a former Natural Products chemist with the FDA's Division of Natural Products. During the time he was with the agency, it took action against a product only when it received reports of harmful side effects, he says.
Competition may ultimately lead to self-regulation within the industry. Some herbal product companies are now hiring independent laboratories to test their competitor's products, then releasing the results to health food stores, says Rob McCaleb, president of the Herb Research Foundation in Boulder, Colo. But it's not yet clear what stores will do with this information.
Know Your Brands
In the meantime, your best bet may be to buy herbs from a company you know. "A company that has a long-standing reputation of quality with consumers is unlikely to risk that reputation by knowingly cheating on ingredients," says McCaleb.
That doesn't mean looking for the most expensive brands. "There's such a wide range of prices out there, it's hard to equate quality and cost," says McCaleb. However, a product that seems too good to be true in terms of cost is probably a low-quality extract.
When possible, you should look for the brands used in clinical trials, says Obermeyer. After all, that's the product that has been most proven to work. And clinical proof is particularly important with herbal medicines, says McCaleb, because unlike most over-the-counter drugs, you might have to take them for a long time before they take effect. "If a product is substandard, it could take years to find out you've wasted your money and also the opportunity to protect your body."
Read packaging carefully. Any research claims should be made specifically for the product you are considering -- not just for the herb in general. Some manufacturers print "clinically proven" or the equivalent on their boxes. When you look more closely, you may find it was someone else's St. John's Wort or ginkgo biloba that was studied, not the brand you have in your hands.
"Self-care requires self-education," said McCaleb. That means reading up on herbs, their uses, research, dosages and side effects and who shouldn't be taking them. "Everyone who uses natural products for health care owes it to themselves to learn as much as they can about the supplements."