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Milk Thistle For Liver Detoxification?
| Milk thistle is an herbaceous annual or biennial plant with
a dense prickly flower head with purplish tubular flowers. |
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Milk thistle is an
edible plant native to southern Europe, southern Russia, Asia Minor,
and nothern Africa, and has been used for food in the countries
surrounding the Mediterranean for a long time as well as a tonic herb
for the liver. Virtually all parts of the plant have been used as food
with no known toxicity. Milk thistle was introduced to North America by
European colonists.
Today, milk
thistle is best known as a producer of liver protectant known as
silymarin, a group of milk thistle flavonoids. The milk thistle in
commerce is a standardized extracts prepared from the fruits (seeds) of
Silybum marianum. Like Ginkgo biloba, milk thistle is required to be
standardized and rendered to concentrated forms to be effectively used
for desired medicinal purposes, which, in this case, is as a
hepatoprotectant. In general, milk thistle extracts are standardized to
a concentration of 70-80% of flavone lignans including isosilybinin,
silybinin, silychristin, and silydianin, which are collectively called
silymarin.
Milk Thistle For
Liver Detoxification
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Milk thistle has been known in Europe and other
Mediterranean countries since ancient times. Theophrastus mentioned
about milk thistle around 4th century, B.C. Dioscorides wrote about the
medicinal value of milk thistle, and Pliny the Elder wrote on the
improvement of bile flow by milk thistle, calling it "Silybum" around
the 1st century, A.D. Nicholas Culpeper, an English herbalist mentioned
in 1650 that milk thistle is effective for removing liver obstructions. |
Von Haller documented the use of milk
thistle for liver ailments in 1744. Milk thistle has been mentioned as
a folkloric remedy for asthma, cancer, catarrh, chest pains, dropsy, fever,
hepatitis, rabies, jaundice, vaginal discharge, malaria, plague,
spasms, and spleen problems. Milk thistle has been under scientific and
clinical investigation since turn of the last century, mainly in
Germany. In the 1960s, German scientists identified a group of active
ingredients from milk thistle, mainly from the seeds, and named them
collectively as "silymarin". The preparation of milk thistle fruits and
seeds were approved by German Commission E as a highly safe and
effective herb for liver health.
Usage
German Commission E approved the internal
use of crude milk thistle fruit preparations for dyspeptic complaints.
Standardized extracts (usually ranging in silymarin concentration from
70 to 80%) are approved for toxic liver damage and as a supportive
treatment for chronic inflammatory liver disease and hepatic cirrhosis.
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Silymarin
is known to protect the liver by altering and strengthening the
structure of outer cell membranes of hepatocytes (liver cells),
preventing toxins from entering the liver cells, and by stimulating the
regenerative ability of the liver and the formation of new hepatocytes
through the activation of an enzyme nucleolar polymerase A, which leads
to the increase in ribosomal protein synthesis and cell division. |
Silymarin, as an
anti-oxidant, may also reduce damages to liver cells caused by chronic
use of certain prescription drugs. The silybin component of sillymarin
has been related to cholesterol-lowering effects. Through the
capability to increase bile solubility, sylimarin may also help prevent
or alleviate gallstones.
Dose: 12-15 grams
per day of powdered seed is recommended for making infusions or other
preparations to be taken orally. For standardized extract, 200-400 mg
of silymarine per day is recommended.
Side Effects: No
side effects are known for crude preparation, as milk thistle is a
food, and a relative of artichoke. For standardized extract with high
concentration of sylimarine, a mild laxative effect has been observed
occasionally.
Chemistry and
Pharmacology Of Milk Thistle
A rather complete chemical composition
list of milk thistle can be found in Dr. Duke's Phytochemical and
Ethnobotanical Databases. Milk thisle seeds contain 1.5-3%
flavonolignans, collectively called silymarin; 20-30% fixed oils, of
which approximately 60% is linoleic acid, approximately 30% is oleic
acid, and approximately 9% is palmitic acid; 25-30% protein; 0.038%
tocopherol; 0.63% sterols, including choleterol, campeterol,
stigmasterol, and sitosterol; and some mucilage. [Herbal Medicine -
Expanded Commission E monographs, by Mark Blumenthal, Alicia Goldberg,
and Josef Brinckmann, first edition, 2000]. Silymarin's constituents
are isosilybinin, silybinin, silychristin, and silydianin, of which
silybinin accounts for approximately 50% of silymarin. [Dr. Duke's
Essential Herbs, by James A Duke, 1999].
There have been
very few clinical tests on milk thistle or any herb for women at
pregnancy. Thus, although an extremely safe herb and food, milk thistle
is recommended against women who are pregnant or lactating largely due
to the lack of data and our ignorance.
Milk Thistle
Protects Liver Function
As a mild food and herb, milk thistle's
anecdotes and folklores may not be as fancy and splendid as those of
ginseng or ginkgo. Unlike the latter two herbs, milk tistle is strictly
non-Asian, and has been used in the regions surrounding the
Mediterranean. Medicinal efficacies of milk thistle fruits and seeds
for protecting the liver and helping with various ailments associated
with liver function have been known and exploited for more than two
thousand years, even before the preparation methods for standardized
extracts were available.
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