Milk Thistle: An Herb of Many Benefits
By Elizabeth Hall

Because it spreads so easily, many farmers might be tempted to treat milk thistle as a noxious weed. But this plant's virtues actually deem it most beneficial and valuable. It has, like its cousin the globe artichoke, been used as a tasty food. In fact, boiled young milk thistle flowers taste very much like artichokes. All other parts of the plants can be used as food, too. High in protein and the essential fat, linoleic acid, milk thistle seeds are also nutritious.⁽¹⁾ 

The plant grows five to ten feet high, displaying reddish-purple, spiny flowers. Its name comes from both the white markings on leaves and its white sap, which was traditionally used to increase lactation. Milk thistle is not to be confused with blessed thistle, although they do share some medicinal properties.

Originating in the Mediterranean region of Europe, the herb is now found growing wild in California and the eastern United States. It is also commercially cultivated in Texas and Argentina for the phytochemical, silymarin-one of its most valuable medicinal properties.
Historically, the ancient Greeks and Romans surmised that milk thistle was healing medicine for an ailing liver and they were so right, as we shall shortly see.

Milk Thistle a Mighty Antioxidant
Milk thistle is a potent antioxidant which destroys free radicals. Free radicals that are not contained in the power plants of cells (mitochondria) or in the cells' garbage disposals, damage membranes of cells, DNA, and other essential molecules in the body. In fact, free-radical damage has been indicted for at least 50 chronic diseases! Some studies show that the antioxidant quality of milk thistle is almost 10 times as powerful as that of vitamin E. Protecting the integrity of the cell's membranes is important because these membranes shield the contents of the cells from free-radical damage.

Milk Thistle The Liver's Friend
Because the liver breaks down many drugs and cancer-producing agents, it is a hot-bed of free-radical generation. Scientific studies show that milk thistle helps to protect the liver not only from free radicals, but also from toxins that jeopardize its functioning. Similar to its work elsewhere in the body, milk thistle also protects the liver by guarding its cell membranes. For example, animal studies demonstrate that silymarin, the main active ingredient in milk thistle, protects the liver from certain toxins in Death-Cap mushrooms. If these mushrooms are eaten, they damage the liver and can cause certain death.

Other animal studies show that silymarin affords significant protection to the liver from alcohol. A controlled, doubleblind study showed that silymarin reduced elevated liver enzymes, an elevated level of which indicates serious liver damage and disease.⁽²⁾ 

Early studies demonstrate that silymarin can also reduce liver damage caused by certain mind-altering drugs. A word of caution here. Alcohol, obesity, pot-belly fat, diabetes, and depression all injure the liver. The liver cannot fully recover as long as these lifestyle conditions persist. In other words, no herb-however beneficial substitutes for good health habits.

Silymarin increases the liver's content of another important antioxidant, glutathione⁽³⁾ Glutathione is needed for the detoxification of cancer-producing agents. Common lifestyle problems like stress, obesity, toxins, medications, too much dietary fat, and an excessive amount of niacin, all deplete the liver of glutathione. It follows that a modest supplementation of milk thistle could benefit people affected by such conditions-especially when coupled with the adoption of healthful lifestyle practices. Just a note-because the trace mineral selenium is essential to glutathione production, no amount of milk thistle would bolster the liver's glutathione if one's diet contained insufficient selenium.
A variety of studies show that silymarin can be helpful in acute and chronic hepatitis. As in other conditions, it helps to lower elevated liver enzymes seen in hepatitis. Milk thistle also has another compound, silybinin, that stimulates protein synthesis and thus repairs and regenerates liver cells.

A Friend to the Gallbladder, Too
Tucked below the lower edge of the liver is the gallbladder. This organ stores and concentrates the bile which the liver produces. Bile is important, because it physically breaks up (emulsifies) fats, making them more susceptible to digestive enzymes. Sometimes the flow of bile from the gall bladder through its duct leading into the intestine becomes sluggish. Some studies suggest that silymarin improves the excretion of bile from the gallbladder and thus reduces the risk of gallstone formation.⁽⁴⁾ 

Active Ingredients in Milk Thistle Protects the Kidneys
The kidneys are important in removing excesses of certain compounds and electrolytes that could cost us our lives if they were to accumulate above normal levels.
Animal research shows that the active ingredients in milk thistle also protect the kidneys from free radical damage and poisons. For instance, the drug cisplatin is a very powerful agent in the treatment of testicular cancer. It has, however, devastating side-effects, including damaging the nerves and poisoning the kidneys. An infusion of silibinin given before or after the administration of cisplatin significantly reduced damage to the nephrons, the urine-making factories of the kidneys. In addition, milk thistle stimulates overall repair in the kidneys by improving their ability to synthesize proteins.

Milk Thistle An Anti-inflammatory Agent
As an anti-inflammatory agent, milk thistle blocks inflammation in several ways. For example, milk thistle is a natural Cox-2  inhibitor.⁽⁶⁾ Cox-2 is essential in the production of a hormone called PGE-2. Excess amounts of PGE-2 suppress the immune system and spells serious inflammation! Milk thistle, because it is a Cox-2 inhibitor, reduces inflammation. That is good news indeed because inflammation is largely responsible for a whole host of problems caused by Alzheimer's, arthritis, atherosclerosis, cancer, gum disease, obesity, ulcers, liver disease, and diabetes-to name just a few. Topical application of silymarin is especially effective also for many inflammatory problems of the skin.

Milk Thistle A Cancer Preventive
The active constituents found in milk thistle may afford protection from certain cancers. Take skin cancer, for example. The sun's ultraviolet rays that are so useful in killing germs, can actually suppress immune components in the skin, by generating free radicals which damage it-thus encouraging the development of skin
cancer. And so the skin uses antioxidants to protect itself from sun damage.
Animal studies indicate that topical applications of silymarin reduce skin cancer caused by ultraviolet rays.⁽⁷⁾ Additional studies demonstrate that the herb can significantly inhibit the proliferation of skin cells with damaged DNA,⁽⁸⁾ thus again reducing the incidence of skin-cancer. Scientists are now thinking that antioxidants like silymarin should even be added to sunscreens.

Animal studies suggest that silymarin could also reduce or retard the ability of damaged cells to multiply in the colon.(9) Rodent and test-tube studies reveal that silymarin, taken orally, may inhibit the progression of prostate cancer in both its early and advanced stages.^(10),(11) Silymarin seemed to inhibit the growth and DNA synthesis in human breast and cervical carcinoma cells as well. ⁽¹²⁾ 
Tumor cells, in a process known as angiogenesis, send out chemical messengers that encourage the growth of new blood vessels which supply the tumor with fresh blood and nutrients. With this extra blood supply, tumor cells become aggressive in invading adjacent cells. Several animal studies show that silymarin inhibits angiogenesis.⁽¹³⁾ However, as promising as silymarin and other herbs such as turmeric are, they should not be considered as a substitute for preventive care and prompt, early surgery (if indicated) for cancers.

Milk Thistle A Help for Diabetes
It might take several weeks, but milk thistle can reduce high blood-sugar. It can also be helpful in preventing or curtailing several other diabetic complications. Take for example aldose reductase, an enzyme in the eye and many other parts of the body. Aldose reductase changes glucose into a sugar alcohol called sorbitol. Excessive amounts of sorbitol trapped in the eye damage the retina (retinopathy). As excessive amounts of sorbitol accumulate in the nerves as well, it can also damage them (neuropathy). Sometimes the damage is found in the peripheral nerves, such as in the feet. Numbness, tingling, burning, pain, and muscle weakness follow. At other times, neuropathy may occur in the nerves supplying the heart, and electrical disturbances of the heart's rhythm or rate (arrhythmia) result. Early studies suggest that silybin significantly reduces elevated sorbitol levels found in non-insulin dependent diabetic individuals.
A considerable number of people with type 2 diabetes also have elevated plasma levels of insulin. As you remember, insulin facilitates the movement of glucose (necessary for energy production) into cells. For this to happen, insulin molecules must bind to insulin receptors on the cell membranes. In type 2 diabetes, the insulin receptors are damaged, and the blood-sugar level remains high. This elevated level causes the pancreas to continue to make even more insulin. The excess insulin encourages the development of high blood pressure and atherosclerosis. Diabetes also increases the risk of liver damage.

Several studies show that when individuals who had both diabetes and liver damage were given 600 mg. of silymarin daily for 4 months, their elevated plasma glucose levels, their hemoglobin AI levels (another measurement of diabetes), and their elevated level of plasma insulin all significantly dropped. There was also a substantial decrease in MDA (malondiadehyde)* levels in the treated group, compared to the control group. (14) Elevated levels of MDA can mean risk for undesirable blood clotting, nerve damage, and cardiovascular complications. Another animal study demonstrated that silymarin has also been found to both protect the beta-cells in the pancreas (which produce insulin) and encourage their recovery from certain toxins. (15)

Milk Thistle Usage and Cautions
Side-effects from milk thistle are uncommon. However, people who are taking any medications should check with their pharmacist first to prevent any adverse herb-drug interaction. Some people do develop flatulence or diarrhea while taking milk thistle. This diarrhea can usually be corrected by taking a small amount of psyllium fiber.
Because silymarin, does not dissolve well in water, it should not be taken as a tea, but rather in capsule form, with meals. Standardized vegi-caps of milk thistle would be the optimal form, in which the percent of silymarin is indicated. The dose should contain at least 70 percent silymarin, which will provide good amounts of silibinin, too.
Is milk thistle a cure-all? Definitely not, but it does possess many benefits for the liver, kidneys, and body in general, making it a most valuable herb.

Elizabeth Hall has taught and researched health topics for more than 25 years at Wildwood Lifestyle Center & Hospital, Wildwood, Georgia.

This Article is courtesy of the Journal of Health and Healing. If you would like the full Journal or simply more information check out our Journal of Health & Healing section of the website.

*MDAis a highly toxic by-product formed by action of free radicals on fats and cholesterol. Its concentration is especially elevated in individuals with diabetes. This is unfortunate because MDA can cause permanent damage to DNA, tissues, and the fat-like components found in the cell membranes.

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