& American Ginseng
is widely used in the U.S. as a dietary supplement by consumers seeking to
improve general energy and vitality, particularly during times of fatigue or
stress. The most commonly used type of ginseng is Asian ginseng (Panax ginseng
C.A., Meyer), often sold as Panax, Chinese, or Korean ginseng. Closely related
to Asian ginseng is American ginseng (Panax quinquefolius L.), which is
sometimes preferred for its milder effects. Siberian ginseng, also called
eleuthero (Eleutherococcus senticosus Rupr ex Maxim), is not as closely related
to the other two, is often considered somewhat weaker in action, and is a less
Other reported uses of ginseng include
normalizing blood sugars, such as in diabetes, stimulating immune function, and
treating male impotence. Biologically, ginseng has been shown to allow cells to
more readily use stored sugar, enabling red blood cells to carry more oxygen.
However, the clinical evidence for ginseng's effectiveness has been
Ginseng-containing dietary supplements are
typically made from a powder or extract of ginseng root. Plant chemicals called
ginsenosides are believed to play a role in ginseng's activity. They are
considered "marker" compounds for ginseng, i.e., their presence (or absence)
and their profiles can indicate the type and quality of ginseng present in a
Safety concerns have been raised over
potential pesticide and heavy metal contamination in some botanical products.
For example, the pesticide pentachloronitrobenzene (known as quintozene or
PCNB), a possible carcinogen that may also be toxic to the liver and kidney and
impair oxygen transport in the blood, has been reported in samples of ginseng.
However, neither the FDA nor any other federal or state agency routinely tests
ginseng products, or other supplements, for quality prior to sale.
ConsumerLab.com, as part of its mission to
independently evaluate products that affect health, wellness, and nutrition,
purchased many of the leading Asian and American ginseng dietary supplements
sold in the U.S. and tested them for identity, quality and
Results: In April and May 2000, ConsumerLab.com purchased a
total of 22 brands of Asian and American ginseng products to determine whether
they possessed 100% of the claimed amounts and types of ginseng. If the type or
amount of ginseng was not clearly labeled, products were held to specific
minimum standards selected by ConsumerLab.com.
Products were also required to meet purity
requirements for heavy metals (lead, arsenic, and cadmium) and the pesticides
hexachlorobenzene, quintozene, and lindane. Hexachlorobenzene is a
probable human carcinogen and has been banned from most food crop use
throughout the world. Quintozene and lindane are potential carcinogens that may
also be toxic to various organs and are generally not allowed for use on food
products in the U.S.
Seventeen of these products were Asian
(labeled as Panax ginseng, Asian ginseng, Chinese ginseng, or Korean ginseng),
four were American ginseng, and one was a mixture of Asian, American, and
Siberian ginseng. One of the American ginseng products made of root powder was
immediately eliminated from further testing as it was it was labeled to contain
only 0.589% ginsenosides, which is below the 2.0% minimum for American ginseng
root powder required to pass ConsumerLab.com testing. The remaining twenty-one
products were tested.
Only nine products tested met all of
ConsumerLab.com's criteria for ginseng quality and purity. Each of these nine
passing products was also found to meet the State of California's stringent
standard for lead levels.
Among the twenty-one
twelve did not pass testing
as they did not pass one
or more criteria.
Eight products contained
unacceptable levels of both quintozene and hexachlorobenzene. Two of these
products had levels of these pesticides more than twenty times the allowed
amount. None of the products tested surpassed the limit for the pesticide
Two products contained
lead above the acceptable level (3 micrograms per daily serving). None of the
products tested, however, were found to contain significant levels of arsenic
Seven products had less
than the required concentration of ginsenosides.
In summary, out of the
twenty-two products evaluated (including the one product dropped from testing
as described above), 9 products passed all three general criteria (i.e.,
ginsensosides, pesticides, and heavy metals) while 5 failed two criteria and 8
failed a single criterion.
Interestingly, all eight of
the products that contained lead or pesticides were labeled as containing
"Korean" ginseng. In fact, only 2 of the 12 products containing Korean ginseng
passed. Among the eight Korean ginseng products contaminated with pesticides
three also had low ginsenoside levels and two others had high lead levels. Two
Korean ginseng-containing products failed solely on low ginsenoside