Nutritional Supplement

Milk Thistle

Also indexed as: Carduus marianus, Silybum marianum

  • Blood Sugar and Diabetes Support

    Type 2 Diabetes

    Supplementing with milk thistle extract may improve blood glucose levels, HbA1c, and insulin sensitivity, and reduce oxidative stress and inflammation.
    Type 2 Diabetes
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    An extract of milk thistle (Silybum marianum) called silymarin, at a dose of 140 mg three times per day, has been shown in placebo-controlled research to improve blood glucose, insulin, and triglyceride levels, and reduce HbA1c and markers of insulin resistance, oxidative stress and systemic inflammation in people with type 2 diabetes.16,17,18 In addition, preliminary research indicates a combination supplement containing silymarin and berberine (a compound found in several medicinal plants including goldenseal [Hydrastis canadensis]) may improve glycemic control and lipid metabolism in people with type 2 diabetes.19,20

  • Digestive Support

    Gallstones

    Milk thistle extracts in capsules or tablets may be beneficial in preventing gallstones.
    Gallstones
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    Milk thistle extracts in capsules or tablets may be beneficial in preventing gallstones. In one study, silymarin (the active component of milk thistle) reduced cholesterol levels in bile,21 which is one important way to reduce gallstone formation. People in the study took 420 mg of silymarin per day.

What Are Star Ratings?
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Reliable and relatively consistent scientific data showing a substantial health benefit.
Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.

Our proprietary “Star-Rating” system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by the medical community, and whether studies have found them to be effective for other people.

For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.

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Traditional Use (May Not Be Supported by Scientific Studies)

Medical use of milk thistle can be traced back more than 2,000 years. Nicholas Culpeper, the well-known 17th-century pharmacist, cited its use for opening “obstructions” of the liver and spleen and recommended it for the treatment of jaundice.

References

1. Wagner H, Horhammer L, Munster R. The chemistry of silymarin (silybin), the active principle of the fruits of Silybum marianum (L.) Gaertn. Arzneim-Forsch Drug Res 1968;18:688-96.

2. Hikino H, Kiso Y, Wagner H, Fiebig M. Antihepatotoxic actions of flavonolignans from Silybum marianum fruits. Planta Medica 1984;50:248-50.

3. Faulstich H, Jahn W, Wieland T. Silibinin inhibition of amatoxin uptake in the perfused rat liver. Arzneimittelforschung 1980;30:452-4.

4. Tuchweber B, Sieck R, Trost W. Prevention by silibinin of phalloidin induced hepatotoxicity. Toxicol Appl Pharmacol 1979;51:265-75.

5. Feher J, Lang I, Deak G, et al. Free radicals in tissue damage in liver diseases and therapeutic approach. Tokai J Exp Clin Med 1986;11:121-34.

6. Sonnenbichler J, Zetl I. Stimulating influence of a flavonolignan derivative on proliferation, RNA synthesis and protein synthesis in liver cells. In Assessment and Management of Hepatobiliary Disease, ed. L Okolicsanyi, G Csomos, G Crepaldi. Berlin: Springer-Verlag, 1987, 265-72.

7. Schuppan D, Strösser W, Burkard G, Walosek G. Legalon® lessens fibrosing activity in patients with chronic liver diseases. Zeits Allgemeinmed 1998;74:577-84.

8. Salmi HA, Sarna S. Effect of silymarin on chemical, functional and morphological alterations of the liver. A double-blind controlled study. Scand J Gastroenterol 1982;17:517-21.

9. Leng-Peschlow E. Alcohol-related liver diseases-use of Legalon®. Z Klin Med 1994;2:22-7.

10. Ferenci P, Dragosics B, Dittrich H, et al. Randomized controlled trial of silymarin treatment in patients with cirrhosis of the liver. J Hepatol 1989;9:105-13.

11. Velussi M, Cernogoi AM, De Monte A, et al. Long-term (12 months) treatment with an antioxidant drug (silymarin) is effective on hyperinsulinemia, exogenous insulin need and malondialdehyde levels in cirrhotic diabetic patients. J Hepatology 1997;26:871-9.

12. Parés A, Planas R, Torres M, et al. Effects of silymarin in alcoholic patients with cirrhosis of the liver: results of a controlled, double-blind, randomized and multicenter trial. J Hepatol 1998;28:615-21.

13. Nassuato G, Iemmolo RM, et al. Effect of silibinin on biliary lipid composition. Experimental and clinical study. J Hepatol 1991;12:290-5.

14. Palasciano G, Portinascasa P, Palmieri V, et al. The effect of silymarin on plasma levels of malondialdehyde in patients receiving long-term treatment with psychotropic drugs. Curr Ther Res 1994;S5:S37-45.

15. Allain H, SchĂĽck S, Lebreton S, et al. Aminotransferase levels and silymarin in de novo tacrine-treated patients with Alzheimer's disease. Dementia Geriatr Cogn Disorders 1999;10:181-5.

16. Ebrahimpour-Koujan S, Gargari B, Mobasseri M, et al. Lower glycemic indices and lipid profile among type 2 diabetes mellitus patients who received novel dose of Silybum marianum (L.) Gaertn. (silymarin) extract supplement: A Triple-blinded randomized controlled clinical trial. Phytomedicine 2018;44:39–44.

17. Ebrahimpour Koujan S, Gargari B, Mobasseri M, et al. Effects of Silybum marianum (L.) Gaertn. (silymarin) extract supplementation on antioxidant status and hs-CRP in patients with type 2 diabetes mellitus: a randomized, triple-blind, placebo-controlled clinical trial. Phytomedicine 2015;22:290–6.

18. Huseini H, Larijani B, Heshmat R, et al. The efficacy of Silybum marianum (L.) Gaertn. (silymarin) in the treatment of type II diabetes: a randomized, double-blind, placebo-controlled, clinical trial. Phytother Res 2006;20:1036–9.

19. Di Pierro F, Bellone I, Rapacioli G, Putignano P. Clinical role of a fixed combination of standardized Berberis aristata and Silybum marianum extracts in diabetic and hypercholesterolemic patients intolerant to statins. Diabetes Metab Syndr Obes 2015;8:89–96.

20. Di Pierro F, Putignano P, Villanova N, et al. Preliminary study about the possible glycemic clinical advantage in using a fixed combination of Berberis aristata and Silybum marianum standardized extracts versus only Berberis aristata in patients with type 2 diabetes. Clin Pharmacol 2013;5:167–74.

21. Nassuato G, Iemmolo RM, et al. Effect of silibinin on biliary lipid composition. Experimental and clinical study. J Hepatol 1991;12:290-5.

22. Brown DJ. Herbal Prescriptions for Better Health. Rocklin, CA: Prima Publishing, 1996, 151-8.

23. Reyes H. The spectrum of liver and gastrointestinal disease seen in cholestasis of pregnancy. Gastroert Clin N Am 1992;21:905-21.

24. Adverse Drug Reactions Advisory Committee. An adverse reaction to the herbal medication milk thistle (Silybum marianum). MJA 1999;170:218-9.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.