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 You're 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™).

MILK THISTLE (SILYBUM MARIANUM)

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.

WHAT IS MILK THISTLE USED FOR TODAY?

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.

Top

WHAT IS THE SCIENTIFIC EVIDENCE FOR MILK THISTLE?

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

Top

DOSAGES

The standard dosage of Milk Thistle is 200 mg 2 to 3 times a day of an extract standardized to contain 70% silymarin.

There is some evidence that silymarin bound to phosphatidylcholine may be better absorbed.26,27 This form should be taken at a dosage of 100 to 200 mg twice a day.

Warning: Considering the severe nature of liver disease, a doctor's supervision is essential. Also, do not inject Milk Thistle preparations that are designed for oral use!

Top

SAFETY ISSUES

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.

Top

INTERACTIONS YOU SHOULD KNOW ABOUT

If you are taking:

• Oral contraceptives: Milk thistle may reduce their effectiveness.

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

Top

References:

1. Schulz V, et al. Rational phytotherapy. New York: Springer-Verlag, 1998: 215.

2. Muriel P, et al. Silymarin protects against paracetamol-induced lipid peroxidation and liver damage. J Appt Toxicol 12: 6439-6442, 1992.

3. Paulova J, et al. Verification of the hepatoprotective and therapeutic effect of silyrnarin in experimental liver injury with tetrachloromethane in dogs. Vet Med (Praha) 35(10): 629-635, 1990.

4. Skakun NP, et al. Clinical pharmacology of Fegalon (review of the literature). Vrach Delo 5: 5-10, 1988.

5. Tuchweber B, et al. Prevention of silybin of phalloidin-induced acute hepatotoxicity. Toxicol Appl Pharmacol 51(2): 265-275, 1979.

6. Boari C, et al. Toxic occupational liver diseases. Therapeutic effects of silymarin. Minerva Med 72(40): 2679-2688,1981.

7. Szilard S. Protective effect of Legalon in workers exposed to organic solvents. Acta Med Hung 45(2): 249-256,1988.

8. Rui YC. Advances in pharmacological studies of silymarin. Mem Inst Osivaldo Cruz 86(Suppl. 2): 79-85, 1991.

9. Schulz V, et al. Rational phytotherapy. New York: Springer-Verlag, 1998: 216.

10. Hikino H, et al. Natural products for liver disease. As cited in Wagner H, et al. Economic and medicinal plant research, Vol 2. New York: Academic Press, 1988: 39-72.

11. Muzes G, et al. Effects of silymarin (Legalon) therapy on the antioxidant defense mechanism and lipid peroxidation in alcoholic liver disease (double-blind protocol). Orv Hetil 131(16): 863-866, 1990.

12. Giannola C, et al. A two-center study on the effects of silymarin in pregnant women and adult patients with so-called minor hepatic insufficiency. Clin Ther 114(2): 129-135,1985.

13. Schulz V, et al. Rational phytotherapy. New York: Springer-Verlag, 1998: 218.

14. Berenguer J, et al. Double-blind trial of silymarin vs. placebo in the treatment of chronic hepatitis. Munch Med Wochenschr 119: 240-260, 1977.

15. Buzzelli G, et al. A pilot study on the liver protective effect of silybin-phosphatidylcholine complex (IdB 1016) in chronic active hepatitis. Int J Clin Pharmacol Ther Toxicol 31(9): 456-460, 1993.

16. Liruss F, et al. Cytoprotection in the nineties: Experience with ursodeoxycholic acid and silymarin in chronic liver disease. Acta Physiol Hung 80(1-4): 363-367,1992.

17. Magliulo E, et al. Results of a double blind study on the effect of silvinarin in the treatment of acute viral hepatitis, carried out at two medical centers. Med Klin 73:28-29,1060-1065,1978.

18. Bode JC, et al. Silymarin for the treatment of acute viral hepatitis? Report of a controlled trial. Med Min 72(12): 513-518, 1977.

19. Salim H, et al. Effect of silymarin on chemical, functional and morphological alterations of the liver. ScandJ Gastroenterol 17: 517-521, 1982.

20. Feher J. Liver protective action of silymarin therapy in chronic alcoholic liver diseases. Orv Hetil 130(51): 2723-2727,1989.

21. Trinchet JC. Treatment of alcoholic hepatitis with silymarin. A double-blind comparative study in 116 patients. Gastroenterol Clin Biol 13(2): 120-124, 1989.

22. Bunout D, et al. Controlled study of the effect of silymarin on alcoholic liver disease. Rev Med Chil 120(12): 1370-1375, 1992.

23. Ferenci P, et al. Randomized controlled trial of silymarin treatment in patients with cirrhosis of the liver. J Hepatol 9: 105-113, 1989.

24. Pares A, et al. Effects of silymarin in alcoholic patients with cirrhosis of the liver: Results of a controlled, double-blind, randomized and multicenter trial. J Hepatology 28: 615-621, 1998.

25. Brinker F. Herb contraindications and drug interactions, 2nd ed. Sandy, Oregon: Eclectic Medical Publications, 1998: 103.

26. Schandalik R, et al. Pharmacokinctics of silybin in bile following administration of silipide and silymarin in cholecsytectomy patients. Arneimittelforschung 42(7): 964-968,1992.

27. Barzaghi N, et al. Pharmacokinetic studies on IdB 1016, a silybin-phosphatidylchohne complex in healthy human subjects. Eur J Drug Metab Pharmacokinet 15(4): 333-338, 1990.

28. Awang D. Milk thistle. Can Pharm J 422: 403-404, 1983.

29. Albrecht M. Therapy of toxic liver pathologies with Legalon. Z Klin Med 47(2): 87-92, 1992.

30. Giannola C, et al. A two-center study on the effects of silymarin in pregnant women and adult patients with so-called minor hepatic insufficiency. Clin Ther 114(2): 129-135,1985.

31. Kim DH, et al. Silymarin and its components are inhibitors of beta-glucuronidase. Biol Pharm Bull 17(3): 443-445,1994.

Top