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FRIDAY, Jan. 4 (HealthScoutNews) -- Some of the six
best-selling herbal treatments may not live up to their claims,
and one may be useless, a new report says.
The study, conducted by noted British alternative
medicine researcher Dr. Edzard Ernst, looked at a compilation of
medical literature on gingko biloba, St. John's wort, echinacea,
ginseng, saw palmetto and kava, which together ring up more than
$590 million in sales annually in the United States alone.
His study appears in the current issue of The Annals
of Internal Medicine.
The study results aren't surprising, says another
alternative medicine expert, Dr. James Dillard, clinical medical
advisor at the Rosenthal Center of Alternative and Complementary
Medicine at Columbia University in New York City.
"Doctors who are familiar with prescribing these treatments
are well aware of what the studies show, and both the value of these
treatments and their limitations," says Dillard.
"However, I think the study is very valuable for physicians
who have not had the opportunity to research these treatments, or
especially for those consumers who may be self-treating without
knowing what they can expect in terms of proven results," he says.
Of the six herbs, the one that came up the clear loser
in Ernst's study was ginseng.
"Well-conducted clinical trials do not support the
efficacy of ginseng to treat any condition," he writes, adding 16
clinical trials used ginseng for a variety of ailments, and all
yielded poor results.
Ernst's research also indicated ginseng's potential
for adverse effects, including insomnia, diarrhea, vaginal bleeding,
severe headaches, hypertension, hypotension, and nausea.
People with heart disease, blood pressure problems
or diabetes should avoid the herb, Dillard says.
He's unwilling, however, to write off ginseng. In
China, it's used as a kind of tonic, much like a multivitamin, Dillard
explains.
"I'm not sure it's fair to say it has no useful effects
just because it was not shown to be effective as a treatment for
specific illnesses. Thousands of years of use in Chinese medicine
can't be simply ignored, based on these few clinical trials," he
says.
The study relied on a systematic review of all published
randomized clinical trials, as well as reports from nine recognized
experts in the field of alternative medicine and the author's personal
database of medical articles.
In addition to the discoveries about ginseng, the
study also found the following:
Gingko biloba: The results of 77 trials involving some
14,000 patients showed this herb was of questionable value for
memory loss and tinnitus -- ringing in the ears. However, it can
help treat dementia and intermittent claudication, pain in the
legs from a lack of blood flow. Side effects include gastrointestinal
problems and headache.
St. John's wort: A total of 57 trials that included nearly
6,000 patients found this herb worked well for mild to moderate
depression. However, there can be problems if it's used with other
drugs, such as anticoagulants, birth control pills and anti-viral
agents.
Echinacea: Sixteen clinical trials featuring nearly 3,400
patients found it helped prevent upper respiratory infections,
although the nature of the studies were such that the findings
are still considered inconclusive, says Ernst. People with systemic
progressive conditions, such as HIV infection, and autoimmune
diseases, such as lupus; multiple sclerosis and tuberculosis,
should not take this herb. The study also recommends it not be
used for more than eight consecutive weeks.
Saw palmetto: This one was the clear winner. Eighteen
trials featuring nearly 3,000 patients revealed saw palmetto reduced
the symptoms of benign prostatic hyperplasia, a non-malignant
condition in which the prostate enlarges as a man ages. Side effects
can include decreased libido, diarrhea, headache, high blood pressure,
nausea and urine retention.
Kava: Here was another winner. Seven trials, involving
377 patients, found this herb worked as a short-term therapy for
anxiety. Side effects can include dizziness, gastrointestinal
discomfort and liver disease. It should not be used by children
under age 12.
In the final analysis, Ernst says his research demonstrates
the need for more rigorous study of all herbal treatments.
Dillard is quick to agree.
"The information we have about many herbal products
thus far is good -- some better than others. Still, it is clear
that we must accumulate the same kind of clinical trial numbers,
including the number of patients, that we find necessary and essential
for the approval of traditional medications, including over-the-counter
treatments," Dillard says.
What To Do
For more information on how to choose an herbal supplement,
visit the American
Botanical Council or the Herb
Research Foundation.
For a rundown on herbs safe to use during pregnancy,
visit GardenGuides.
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