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Other common
name(s): Panax ginseng, Asian ginseng, Oriental ginseng,
Chinese ginseng, Japanese ginseng, Korean ginseng, American ginseng,
man root
Scientific/medical
name(s): Panax
ginseng C. A. Meyer, Panax
quinquefolius
Description
Asian ginseng (Panax
ginseng) is a perennial plant grown in China, Korea,
Japan, and Russia. American ginseng (Panax quinquefolius),
a plant with similar properties, is grown mainly in the United States.
The dried roots of the plants are used in some traditional medicines to
treat a variety of conditions, including cancer. The ginseng plants of
the Panax group discussed here should not be confused with Siberian
ginseng (also known as eleuthero), which has different properties (see
our document Eleuthero).
Overview
Available scientific evidence does not support claims that
ginseng is effective in preventing or treating cancer in humans.
Studies done in the laboratory suggest some substances in ginseng may
have anticancer properties, and some population studies in Asia link it
to lower cancer risk. Clinical trials are still needed to determine
whether it is effective in people. Ginseng should be used cautiously,
as it can cause undesirable side effects in high doses and may even be
dangerous when taken with certain medicines or if the patient is
undergoing surgery.
How is it promoted for use?
Ginseng is an ancient herb that is claimed to help the body
prevent and fight diseases, including cancer. Promoters claim ginseng
enhances athletic performance and provides energy to people who are
stressed or fatigued. It is sometimes used during recovery from
illness. There are also claims ginseng relieves depression and anxiety,
protects the heart, strengthens digestive functions, prevents hardening
of the arteries, stabilizes blood pressure and insulin levels, helps
with erectile dysfunction, and even delays the effects of aging.
What does it involve?
Ginseng is available as a powder, capsule, tea, or is
sometimes sold already mixed with foods. There is no standard dosage;
however, Commission E (Germany's regulatory agency for herbs) suggests
taking 1 to 2 grams per day of ginseng root for up to 3 months.
There is some variation in quality and strength among ginseng
products. Since it is expensive, some packagers may dilute it or
substitute less expensive ingredients to make it affordable to the
consumer. Some ginseng products from areas of the world such as
Siberia, Alaska, and Brazil are mislabeled. True ginseng has the word
Panax as part of its Latin, or scientific, name. A 1978 study of 54
ginseng products found that one quarter of them contained no ginseng at
all, although the content of products may be more reliable today.
What is the history behind it?
The Chinese have been using ginseng for thousands of years as
an herbal remedy. Early Chinese books listing curative foods claimed
ginseng could enlighten the mind and increase wisdom. The Chinese also
used ginseng to treat ailments of the digestive and respiratory
systems, nervous disorders, diabetes, to keep the elderly warm in
winter, and to increase energy and improve memory. The life-prolonging
effects of ginseng were first described during China's Liang Dynasty
(220–589 AD).
North American ginseng was discovered growing in the mountains
of Quebec by a Jesuit priest in the early 1700s. It was soon exported
to China, where its medicinal value was appreciated. Other variations
of ginseng are grown in Korea and Japan. Ginseng was not used in
Western medicine until the 1950s, when scientists in the Soviet Union
began studying its health benefits and concluded that it was an
"adaptogen"—that is, something that helps the body adapt to
outside stresses and ward off disease. The Vietcong used it extensively
to treat gunshot wounds during the Vietnam War.
In 1978, Taik-Koo Yun, MD, from the Korea Cancer Center
Hospital in Seoul, began to conduct population-based studies to
investigate whether ginseng had anticancer properties. He has published
articles arguing that ginseng can prevent most cancers, but he is not
certain how this occurs. He has encouraged more worldwide study of this
herb.
What is the evidence?
Ginseng has been known for three thousand years, but despite a
good deal of research, scientists still are not certain whether the
herb can help prevent or treat cancer. Most studies of ginseng have
been done in China and Korea, and only recently has it received more
research attention in Western countries.
The medicinal effects of ginseng are thought to be due to a
group of about two dozen substances in the root called ginsenosides,
which resemble steroid hormones. In laboratory research using cell
cultures and animals, some ginsenosides have been shown to boost the
immune system or slow the growth of cancer cells. Some may also have
anti-inflammatory and antioxidant effects. Whether these properties
will translate into anticancer activity in humans is still not clear,
as few human studies have been done.
Several case-control studies done in Korea have found that
people who took ginseng extract seemed to have a lower risk of cancer
overall. One recent Chinese study suggested that women with breast
cancer who used ginseng before their diagnosis survived longer than
those who did not. The same study found that the women who used ginseng
during treatment reported better quality of life than those who did
not. These studies were not are not the most scientifically convincing,
however, and the authors point out that further research is needed to
determine the true benefit of ginseng both in cancer prevention and for
people who have cancer. Researchers are looking at ginseng’s
potential to improve the effectiveness of other cancer treatments, such
as chemotherapy, and are studying its effects on cancer-related
fatigue.
The benefits of ginseng for other medical conditions have not
been shown conclusively, although research is ongoing. Many studies of
this herb have suffered from design problems, and results have been
contradictory. Some scientists have found that it raises blood pressure
while others have reported that it lowers blood pressure. In some
studies, ginsenosides seem to act as stimulants, but in others they
seem to work as sedatives. The only conclusions that can be reached
with any certainty at this time are that ginseng is a complex herb and
that its medicinal effects are not clearly defined.
A systematic review of randomized clinical trials evaluated
the evidence of ginseng root extract’s effectiveness. Based
on data from sixteen studies, the researchers concluded that ginseng
root extract had not been shown to have a significant effect on
physical performance, diabetes, herpes infections, psychomotor
performance, cognitive function, or the immune system. More research
into its medicinal properties is needed.
Are there any possible problems or
complications?
This product is sold as a
dietary supplement in the United States. Unlike companies that produce
drugs (which must provide the FDA with results of detailed testing
showing their product is safe and effective before the drug is approved
for sale), the companies that make supplements do not have to show
evidence of safety or health benefits to the FDA before selling their
products. Supplement products without any reliable scientific evidence
of health benefits may still be sold as long as the companies selling
them do not claim the supplements can prevent, treat, or cure any
specific disease. Some such products may not contain the amount of the
herb or substance that is written on the label, and some may include
other substances (contaminants). Though the FDA has written new rules
to improve the quality of manufacturing processes for dietary
supplements and the accurate listing of supplement ingredients, these
rules do not take full effect until 2010. And, the new rules do not
address the safety of supplement ingredients or their effects on health
when proper manufacturing techniques are used.
Most such
supplements have not been tested to find out if they interact with
medicines, foods, or other herbs and supplements. Even though some
reports of interactions and harmful effects may be published, full
studies of interactions and effects are not often available. Because of
these limitations, any information on ill effects and interactions
below should be considered incomplete.
Ginseng is generally considered safe, although there are some
possible side effects, especially at higher doses. Side effects may
include increased heart rate, nausea, headaches, trouble sleeping, and
restlessness. Possible effects in women may include swollen breasts and
vaginal bleeding. Ginseng may lower blood sugar levels, a side effect
that could be of particular importance to people taking medicine for
diabetes.
Because ginseng may have steroid hormone–like
effects, some doctors caution against its use in women who have had
breast or endometrial cancer. Not enough study has been done to show
whether ginseng is safe for women who are pregnant or breast-feeding.
Women who fall into these groups should speak with their doctors before
taking ginseng.
Ginseng can have an effect on how long it takes for bleeding
to stop. This could be an issue if ginseng is taken before surgery or
if the patient is taking drugs that affect blood clotting, such as
aspirin or warfarin (Coumadin).
Ginseng may cause headaches, tremors, and can cause manic
episodes if used with antidepressants known as MAOIs, such as
phenelzine (Nardil). Relying on this type of treatment alone and
avoiding or delaying conventional medical care for cancer may have
serious health consequences.
Additional Resources
More information from your American Cancer
Society
The following information on complementary and alternative
therapies may also be helpful to you. These materials may be found on
our Web site (www.cancer.org)
or ordered from our toll-free number (1-800-ACS-2345).
References
Blumenthal M, ed. The
Complete German Commission E Monographs: Therapeutic Guide to Herbal
Medicines. Austin, TX: American Botanical Council; 1998.
Cui Y, Shu XO, Gao YT, Cai H, Tao MH, Zheng W. Association of
ginseng use with survival and quality of life among breast cancer
patients. Am J Epidemiol.
2006;163:645-653. Epub 2006 Feb 16.
Ginseng (American). Memorial Sloan-Kettering Cancer Center Web
site. http://www.mskcc.org/mskcc/html/69236.cfm. Updated September 26,
2007. Accessed June 5, 2008.
Ginseng (Asian). Memorial Sloan-Kettering Cancer Center Web
site. http://www.mskcc.org/mskcc/html/69237.cfm. Updated September 17,
2007. Accessed June 5, 2008.
Gruenwald J. PDR for Herbal Medicines. 3rd ed. Montvale, NJ:
Thomson PDR; 2004.
Natural Standard. Herbal/plant therapies: ginseng (american ginseng,
asian ginseng, chinese ginseng, korean red ginseng, panax ginseng:
panax spp. including p. ginseng c.c. meyer and p. quinquefolius l.,
excluding eleutherococcus senticosus). Complementary/Integrative
Medicine Education Resources, The University of Texas M.D. Anderson
Cancer Center Web site.
http://www.mdanderson.org/departments/cimer/display.cfm?id=DB3FF279-E763-49C4-9A0F41944C3503AF&method=displayFull.
Accessed June 5, 2008.
O’Hara M, Kiefer D, Farrell K, Kemper K. A review of
12 commonly used medicinal herbs. Arch
Fam Med. 1998;7:523-536.
Spaulding-Albright N. A review of some herbal and related
products commonly used in cancer patients. J Am Diet Assoc.
1997;97:S208-S215.
Vogler BK, Pittler MH, Ernst E. The efficacy of ginseng. A
systematic review of randomized clinical trials. Eur J Clin Pharmacol.
1999;55:567-575.
Yun TK, Choi SY, Yun HY. Epidemiological study on cancer
prevention by ginseng: are all kinds of cancers preventable by ginseng?
J Korean Med Sci.
2001;16 Suppl:S19-S27.
Note: This information may not cover
all possible claims,
uses, actions, precautions, side effects or interactions. It is not
intended as medical advice, and should not be relied upon as a
substitute for consultation with your doctor, who is familiar with your
medical situation.
Last Medical Review: 11/01/2008
Last Revised: 11/01/2008
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