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Herbal Supplements
Face New Scrutiny
By LAURA LANDRO
SEPTEMBER 14, 2010
Source:
http://online.wsj.com/article/SB10001424052748704190704575489812916405630.html?mod=WSJ_hpp_MIDDLENexttoWhatsNewsForth#printMode
Elderberry extract and acai to boost the
immune system. Black cohosh to lessen
the discomforts of menopause. Soy
capsules to prevent bone loss and
prostate cancer.
Many botanical supplements—made from the
seeds, bark, leaves, flowers and stems
of a wide range of plants—have been
widely used as folk remedies for
centuries. Americans have been consuming
growing quantities of the supplements in
hopes of warding off disease and easing
symptoms of various conditions. But
there is scant scientific evidence to
support their health benefits.
Now, the federal government is stepping
up research into the safety and
effectiveness of a wide range of
over-the-counter supplements, including
plant oils, garlic, soy, elderberry,
licorice, black cohosh, St. John's wort
and the Asian herb dong quai. The aim is
to better understand how compounds in
the plants affect health and to help
consumers make more informed choices
about supplements, which can interact
with prescription drugs, cause side
effects or lead to new health risks.
Sales of botanical supplements in the
U.S. topped $5 billion last year, up 17%
from five years earlier, according to
the non-profit American Botanical
Council.
"Sometimes people assume because a
product is natural, it is also safer.
But these compounds can have both
benefits and potential side effects and
we need to understand both of those,"
says Floyd Chilton III, director of the
Center for Botanical Lipids and
Inflammatory Disease Prevention at Wake
Forest University Baptist Medical Center
in Winston-Salem, N.C. Dr. Chilton's
center received a $7.5 million federal
grant to study botanicals, including
whether plant oils such as echium and
borage can help play a role in
preventing cardiovascular disease,
asthma and diabetes.
"People are
using
supplements
for purposes
for which
they were
not
intended,"
such as
treating
health
conditions
they have
self-diagnosed,
or using
multiple
supplements
in
combination
with
prescription
medications,
says
Marguerite
Klein,
director of
the
Botanical
Centers
Research
program at
the National
Institutes
of Health.
One concern,
she says is
the heavy
use by women
of black
cohosh to
treat
menopause
symptoms,
such as hot
flashes.
Limited
research
seems to
support the
black
cohosh's
benefit. But
it isn't
known how
the
botanical
works. Black
cohosh has
been linked
in some
patients to
liver
damage, and
breast-cancer
patients are
often
advised to
avoid using
it because
its effects
on breast
tissue are
unknown.
Helping to
spur the
research
initiative
are the
Office of
Dietary
Supplements
and the
National
Center for
Complementary
and
Alternative
Medicine,
both part of
the National
Institutes
of Health.
The agencies
last month
awarded
grants
totaling
about $37
million to
five dietary
supplement
research
centers,
expanding a
program that
has already
awarded more
than $250
million in
research
grants for
herbs and
botanicals
since 2002.
The NIH is
also funding
research
into
botanical
products
through the
National
Cancer
Institute,
which is
interested
in how
components
in
botanicals
might
influence
cancer risk
and tumor
growth.
Studies funded by the federal grants
have so far shown that chamomile
capsules may help reduce anxiety
compared to a placebo and that an
extract from the milk thistle plant can
interfere with the life cycle of the
hepatitis C virus. They also have
refuted some purported benefits of
botanicals, showing, for instance, that
ginkgo biloba does not prevent heart
attack, stroke, or cancer, or stem
memory loss and that St. John's wort was
no better than a placebo in treating
symptoms of attention deficit
hyperactivity disorder in children and
teens.
Unlike drugs, which must be tested in
clinical trials and approved by the Food
and Drug Administration before they can
be marketed, botanicals and other
supplements don't require regulatory
approval. The FDA in June began
requiring all supplement makers to
follow strict quality manufacturing
standards, but the agency only
periodically inspects plants.
An investigation published in May by the
General Accounting Office found
deceptive marketing practices at a
number of online retailers, including
claims that supplements could prevent or
cure conditions such as diabetes,
cancer, or cardiovascular disease. The
investigation also found trace amounts
of potentially hazardous contaminants,
such as lead or bacteria, in 37 of 40
herbal dietary supplement products it
tested.
Tod Cooperman, president of
ConsumerLab.com, which tests supplement
brands for quality, says the group finds
problems with about 25% of all
supplements, and especially with herbal
products, many with ingredients from
overseas. A recent review of supplements
made from ginseng—commonly taken to
boost energy and vitality—found that 45%
failed quality tests because they didn't
contain the advertised amount of ginseng
or were contaminated with lead. Test
results and other information are
available to members, who pay $30
annually.
Consumers also can find information
about potential uses, benefits and risks
of dietary supplements at federal
websites ods.gov and nccam.gov. Another
government site, Medlineplus.gov, grades
scientific evidence on a variety of
supplements.
William Cefalu, director of the
Pennington Biomedical Research Center at
Louisiana State University in Baton
Rouge, says researchers are only
beginning to understand how thousands of
different compounds in a single plant
may interact, and how the concentration
of a particular plant chemical affects
its potency. For example, peppermint tea
is considered safe to drink, but
peppermint oil, often taken for
irritable bowel syndrome or indigestion,
is much more concentrated and can be
toxic if used in high doses.
Because the potency of wild plants can
vary, some researchers are cultivating
their own. At the Center for Botanical
Interaction Studies at the University of
Missouri in Columbia, 600 types of
soybean seeds are being cultivated to
study different concentrations of the
same compounds in the plants and how
they might work to prevent prostate
cancer. The center is also growing 60
types of elderberries to study the
plant's possible role in boosting the
immune system against infection and
fighting cancer and inflammation in the
body. Center director Dennis Lubahn says
there may be variations in individual
plants that will make a difference in
how well they fight disease. "We've come
a long way from the traditional medicine
woman sampling leaves in the forest," he
says.
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