Excerpt: The Natural Health Bible

The following excerpt about milk thistle is from The Natural Health Bible, From the Most Trusted Source in Health Information, Here is Your A-Z Guide to Over 200 Conditions, Herbs, Vitamins, and Supplements.

This book was published by Prima Health in 1999. The editors are Steven Bratman, M.D. and David Kroll, Ph.D They are principals of The Natural Pharmacist. The book is intended to provide “Science-Based Health Information You Can Trust.”

This is one of the most medically conservative of all the natural health guides on the market today. You must keep in mind that the authors are medical scientists and are certainly more skeptical than an herbalist or holistic health practitioner would be.

They make a point of balancing the good with the bad. They don’t just mention successful studies, they also mention less impressive ones. This makes their overall positive assessment of Milk Thistle particularly more meaningful. And they reference all of the studies they researched, which is extremely valuable.

Incidentally, under the dosages heading, the authors specifically mention the reported superiority of the Phytosome® form of milk thistle extract (as found in Maximum Milk Thistle® and UltraThistle®).


Principal Proposed Uses

Chronic viral hepatitis, acute viral hepatitis, alcoholic liver disease, liver cirrhosis, mushroom poisoning (special intravenous form only), protection from liver-toxic medications

Milk thistle, a spiny-leafed plant with reddish-purple, thistle-shaped flowers, has a long history of use both as a food and a medicine. English gardeners at the turn of the century grew Milk Thistle and used the leaves like lettuce, the stalks like asparagus, the roasted seeds like coffee, and the roots (soaked overnight) like oyster plant.

The seeds, fruit, and leaves of Milk Thistle are used for medicinal purposes. Over 2,000 years ago, Pliny the Elder reported that the juice of Milk Thistle could “carry off bile,” an insight that foreshadowed its modern uses. In Europe, the herb was widely used through the early twentieth century for the treatment of jaundice as well as for insufficient breast milk.



Based on the extensive folk use of Milk Thistle in cases of jaundice, European medical researchers began to investigate its medicinal effects. The results led Germany’s Commission E to approve an oral extract of Milk Thistle as a treatment for liver disease in 1986.

It is widely used to treat alcoholic hepatitis, alcoholic fatty liver, liver cirrhosis, liver poisoning, and viral hepatitis, as well as to protect the liver from the effects of liver-toxic medications. Milk thistle is one of the few herbs that have no real equivalent in the world of conventional medicine.

According to reports and some research evidence that we’ll review in the next section, treatment produces a modest improvement in symptoms of chronic liver disease, such as nausea, weakness, loss of appetite, fatigue, and pain. Liver enzymes as measured by blood tests frequently improve, and if a liver biopsy is performed, there may be improvements on the cellular level. Some studies have shown a reduction in death rate among those with serious liver disease.

The active ingredients in Milk Thistle appear to be four substances known collectively as silymarin, of which the most potent is named silybinin.1 When injected intravenously, silybinin is one of the few known antidotes to poisoning by the deathcap mushroom, Amanita phalloides. Animal studies suggest that Milk Thistle extracts can also protect against many other poisonous substances, from toluene to the drug acetaminophen.2-8

Silymarin appears to function by displacing toxins trying to bind to the liver as well as by causing the liver to regenerate more quickly.9 It may also scavenge free radicals and stabilize liver cell membranes.10,11

However, Milk Thistle is not effective in treating advanced liver cirrhosis, and only the intravenous form can counter mushroom poisoning.

In Europe, Milk Thistle is often added as extra protection when patients are given medications known to cause liver problems.

Milk thistle is also used in a vague condition known as minor hepatic insufficiency, or “sluggish liver.”12 This term is mostly used by European physicians and American naturopathic practitioners-conventional physicians don’t recognize it. Symptoms are supposed to include aching under the ribs, fatigue, unhealthy skin appearance, general malaise, constipation, premenstrual syndrome, chemical sensitivities, and allergies.

Milk thistle is also sometimes recommended for gallstones and psoriasis, but there is little to no evidence as yet that it really works for these conditions.



There is considerable evidence from studies in animals that Milk Thistle can protect the liver from numerous toxins. However, human studies of people suffering from various liver diseases have yielded mixed results.

Deathcap Poisoning

In Amanita mushroom poisoning, silybinin appears to dramatically reduce death rates, which are typically from 30 to 50%, down to less than 10%.13 This mushroom destroys the liver if left untreated. In conditions like this one, it isn’t ethical to perform double-blind studies. However, Milk Thistle seems to be so dramatically effective that its value is not disputed.

Chronic Viral Hepatitis

Preliminary double-blind studies of people with chronic viral hepatitis have found that Milk Thistle can produce significant improvement in symptoms such as fatigue, reduced appetite, and abdominal discomfort, as well as results on blood tests for liver inflammation. 14,15,16

Acute Viral Hepatitis

While good results have been reported in one study of 57 people with acute viral hepatitis,17 another study of 151 participants showed no benefit.18

Alcoholic Liver Disease

A 1981 double-blind study followed 106 Finnish soldiers with mild alcoholic liver disease. In the treated group, there was a significant improvement in liver function as measured by blood tests and biopsy.19 Another study reported similar results.20 However, a study of 116 participants showed little to no benefit,21 as did another study of 72 people followed for 15 months.22

Liver Cirrhosis

A controlled study followed 170 people with liver cirrhosis for 3 to 6 years. In the treated group, the 4-year survival rate was 58% as compared to only 38% in the placebo group.23 However, a recently reported 2-year double-blind study of 200 alcoholics with cirrhosis found no benefit.24

Protection from Medications That Damage the Liver

Numerous medications can injure or inflame the liver. Preliminary evidence suggests that milk thistle might protect against liver toxicity caused by such drugs as acetaminophen, dilantin, alcohol, and phenothiazines.25



Milk thistle is believed to possess very little toxicity. Animal studies have not shown any negative effects even when high doses were administered over a long period of time.28

A study of 2,637 participants reported in 1992 showed a low incidence of side effects, limited mainly to mild gastrointestinal disturbance.29

On the basis of its extensive use as a food, Milk Thistle is believed to be safe for pregnant or nursing women and researchers have enrolled pregnant women in studies.30 However, safety in young children, pregnant or nursing women, and individuals with severe renal disease has not been formally established.

No drug interactions are known. However, one report has noted that silybinin (a constituent of silymarin) can inhibit a bacterial enzyme called beta-glucuronidase, which plays a role in the activity of certain drugs, such as oral contraceptives.31 This could reduce their effectiveness.



If you are taking:

• Oral contraceptives: Milk thistle may reduce their effectiveness.

• Medications that could damage the liver: Milk thistle might be protective.


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