Wednesday, March 31, 2004

Lack of research stymies efforts to standardize herbal supplement industry

ANDREW BRIDGES, AP Science Writer

(03-31) 00:02 PST ANAHEIM, Calif. (AP) -- Verifying the quality of the thousands of different botanical extracts sold to U.S. consumers remains difficult because of a lack of basic research into what active ingredients are contained in the herbal supplements and what they do, experts said.

The $4 billion herbal supplement industry peddles extracts from an estimated 3,000 plants, contained in upward of 50,000 products.

Federal law controls how those products are labeled to indicate what ingredients they contain and in what quantities, but the claims don't always withstand scientific scrutiny, said Joseph Betz, of the National Institutes of Health's office of dietary supplements.

"Some of these numbers are wildly inaccurate and some are spot on, right on the money," Betz told reporters Tuesday at the annual meeting of the American Chemical Society.

The problem, Betz said, lies in the nonstandardized analytic methods used to measure the chemical compounds found in the products. "We don't know whether the tests being done are accurate," Betz said. In many cases, the active ingredients in supplements remain unknown, making it difficult to ensure the consistency -- or legitimacy -- of a product.

The raw materials, too, vary in origin, harvest method and how they're mixed with other ingredients. Testing conducted by scientists at Rutgers University revealed that a variety of store-bought herbal supplements didn't match the claims their labels made when subjected to laboratory tests, the university's Mingfu Wang said.

The tests found products that contained: the wrong part of a plant, swapping leaf extracts for those taken from the root; a different species of plant altogether than that listed on the label; detectable levels of drugs, including caffeine, used to spike the supplements, Wang said.

"We found a lot of products didn't match the labels' claims," Wang said.

Analysis of botanical products frequently relies on a single chemical marker to detect a botanical ingredient and assess in what quantities it is present, said Navindra Seeram, of the University of California, Los Angeles.

His laboratory is one of many working to develop a library of chemical "fingerprints" that would allow manufacturers and regulators alike to reliably and accurately analyze herbal products. Already, there are dozens of analytical methods in place for some plant species. For others, there are none, experts said.

Government efforts to develop new analytical methods is prioritized, with safety concerns about a product vaulting it to the top of the list, Betz said. But the work can be slow, especially in a market where products fall in and out of favor relatively quickly -- especially when backed by regulatory action or headline-grabbing deaths, as happened with ephedra.

For instance, two novel methods of testing the herbal stimulant are now being published, just as a federal ban on its sale enters effect, Betz said.

The supplement was enormously popular for weight loss and body building, but drew regulatory scrutiny after it was linked to more than 150 deaths and dozens of heart attacks and strokes.