THURSDAY, Dec. 16 (HealthDay News) -- People have been using herbal supplements for centuries to cure all manner of ills and improve their health. But for all the folk wisdom promoting the use of such plants as St. John's wort and black cohosh, much about their effect on human health remains unknown.
But the federal government is spending millions of dollars to support research dedicated to separating the wheat from the chaff when it comes to herbal supplements.
"A lot of these products are widely used by the consumer, and we don't have evidence one way or the other whether they are safe and effective," said Marguerite Klein, director of the Botanical Research Centers Program at the U.S. National Institutes of Health. "We have a long way to go. It's a big job."
In August, the U.S. National Center for Complementary and Alternative Medicine and the Office of Dietary Supplements awarded about $37 million in grants to five interdisciplinary and collaborative dietary supplement centers across the nation. The grants were part of a decade-long initiative that so far has awarded more than $250 million toward research to look into the safety and efficacy of health products made from the stems, seeds, leaves, bark and flowers of plants.
Reliance on botanical supplements faded in the mid-20th century as doctors began to rely more and more on scientifically tested pharmaceutical drugs to treat their patients, said William Obermeyer, vice president of research for ConsumerLab.com, which tests supplement brands for quality.
But today, herbal remedies and supplements are coming back in a big way. People in the United States spent more than $5 billion on herbal and botanical dietary supplements in 2009, up 22 percent from a decade before, according to the American Botanical Council, a nonprofit research and education organization.
The increase has prompted some concern from doctors and health researchers. There are worries regarding the purity and consistency of supplements, which are not regulated as strictly as pharmaceutical drugs.
"One out of four of the dietary supplements we've quality-tested over the last 11 years failed," Obermeyer said. The failure rate increases to 55 percent, he said, when considering botanical products alone.
Some products contain less than the promoted amount of the supplement in question -- such as a 400-milligram capsule of echinacea containing just 250 milligrams of the herb. Other products are tainted by pesticides or heavy metals.
The U.S. Food and Drug Administration warned supplement makers on Dec. 15 that any company marketing tainted products could face criminal prosecution. The agency was specifically targeting products to promote weight loss, enhance sexual prowess or aid in body building, which it said were "masquerading as dietary supplements" and in some cases were laced with the same active ingredients as approved drugs or were close copies of those drugs or contained synthetic synthetic steroids that don't qualify as dietary ingredients.
But even when someone takes a valid herbal supplement, it may not be as effective when taken as a pill or capsule rather than used in the manner of a folk remedy. For example, an herb normally ground into paste as part of a ceremony might lose its effectiveness if prepared using modern manufacturing methods, Obermeyer said.
"You move away from the traditional use out of convenience, and you may not have the same effect," he said.
Researchers also are concerned that there just isn't a lot of evidence to support the health benefits said to be gained from herbal supplements. People may be misusing them, which can lead to poor health and potential interactions with prescription drugs.
"Consumers often are taking them without telling their doctor, or taking them in lieu of going to the doctor," Klein said.
Botanical research efforts that received recent federal funding include:
Despite the concerns of the medical community, researchers believe there are a lot of valid health benefits that can be derived from botanical supplements. These benefits just need to be proven in the lab.
"We wouldn't be supporting a multi-million dollar program if we didn't feel there was potential," Klein said.
The Office of Dietary Supplements at the U.S. National Institutes of Health has more about herbs and botanical supplements.
SOURCES: Marguerite Klein, M.S., director, Botanical Research Centers Program, U.S. National Institutes of Health, Bethesda, Md.; William Obermeyer, Ph.D., vice president, research, ConsumerLab.com, White Plains, N.Y.; Summer 2010, HerbalGram, American Botanical Council, Austin, Texas
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