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Nov. 19, 1999 (Atlanta) -- For centuries, Native American women used black cohosh to soothe hot flashes. Women today claim that it works, but scientists have little idea why. The mysteries of ancient herbal remedies will soon be probed through rigorous study at the first U.S. botanical research centers.
The University of Illinois at Chicago (UIC) and the University of California, Los Angeles (UCLA) have been selected to receive $1.5 million annually for five years from the NIH. The goal is to produce solid scientific knowledge about herbs, including safety issues, effectiveness, and biological action -- how they work.
"I don't think enough research has been done for both health professionals and consumers to make informed decisions," Christine Swanson of the NIH's Office of Dietary Supplements, which spearheaded the effort along with the National Center for Complementary and Alternative Medicine, tells WebMD. "These research groups are known for their high-quality research as well as their teaching and training background."
Although herbal remedies have a long tradition in Asia and Europe and among indigenous tribes, the scientific study of herbs has been limited at best. Supplements available on U.S. shelves have undergone some scientific study in Western Europe or Japan, but often those studies draw criticism as being biased or otherwise unreliable.
However, where there's smoke there's fire, Norman Farnsworth, a research professor at UIC, tells WebMD in an interview. "There may be deficiencies in every one, but the totality of the findings makes you believe there's something there."
Complicating the situation is the lack of regulation in the supplements industry. Many claims made about herbal supplements range from "reasonably accurate" to "outrageous," says Farnsworth, who will head UIC's new Center for Dietary Supplements Research on Botanicals. "Especially on cable TV, you get outrageous claims that are not supported by any data."
Developing a systematic method for basic science analysis of herbal supplements would be groundbreaking, "flagship" work, says Farnsworth. "We want to establish parameters for doing good, solid scientific work with plant extracts being consumed by humans. Nobody's done this, not even in Europe."
At UIC, the focus will be on herbal supplements used for PMS, menopause, and recurrent bacterial/urinary infections. Ten popular herbal supplements will be studied: black cohosh, red clover, chaste berry, hops, dong quai, Asian ginseng, ginkgo, licorice, cranberry, and valerian.
The UIC center plans to study two herbs each year, identifying active compounds in plant materials, studying how they are metabolized in the human body, and formulating a standardized preparation.
"We want consumers to be sure that what's on the label is what's in the pill," says Farnsworth. "The potency has to be the same, from batch to batch." Compounds that are 'standardized dosage' contain 95-100% of the active ingredient from the plant extract. If the dosage is not standardized, the amount of active ingredient can vary from pill to pill.
All standardized doses will be tested in clinical trials that meet the highest standard in the U.S. -- double-blind, randomized, placebo-controlled trials. Anyone enrolled in a trial will be followed for one year.
"There are 150,000 existing botanicals, but only 1,200 to 1,800 are available as dietary supplements. In terms of preventive medicine, there are many things to be discovered, but we need to apply the high science that we do to drugs," David Heber, who will serve as principal investigator at UCLA's Center for Dietary Supplements Research on Botanicals, tells WebMD in an interview.
Heber, who directs the UCLA Center for Human Nutrition, says that his researchers will explore what makes Chinese red yeast responsible for lowering blood cholesterol, a discovery that may impact heart disease prevention and promote vascular health. The UCLA group will also study the effect of green tea extract and soy in inhibiting tumor growth, which may aid in breast and prostate cancer prevention. In studying St. John's wort, a common herb used for relieving mild depression, UCLA will conduct brain research to track the mechanism of action.
The UCLA group has already conducted a 'market basket' survey, assessing the levels of active ingredients in the more popular herbal supplements already available on store shelves. In analyzing eight major brands of commonly used herbal supplements, the researchers found significant differences in the amounts of active compounds stated on the labels, when compared with what was actually contained in the supplements.
They compared the contents in five commonly used herbal supplements (kava kava, echinacea, saw palmetto, ginseng, and St. John's wort). "The good news is that three of eight manufacturers (Nature's Way, Pharmanex, and Your Life) were able to consistently provide a level of marker and/or active compound in all of their products that reflected what was on the label. Other manufacturers studied included Centrum Herbal, Nature's Resource, Sundown Herbals, Nature's Valley, and Nature's Sunshine," says Heber.
"We're calling for appropriate government oversight of dietary supplements," Heber tells WebMD. "Right now, we have very little action from the FDA. What we need is more oversight in terms of manufacturing standards and labeling, to allow this field to achieve its true potential. We're not calling for overregulation, just for appropriate oversight."
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