Milk Thistle

Milk thistle (Silybum marianum) is an annual or biennial plant native to the Mediterranean region, now widely found on most continents. Milk thistle contains a mixture of isomeric flavonolignans (Silymarin) found in the seeds (fruit).1 (Milk Thistle seeds as considered as the fruit). Almost all seeds used to produce milk thistle extract are now cultivated. The seeds are first ground and then put through an extraction process under controlled temperature conditions. The extract is filtered and then further concentrated and dried under vacuum. It is then combined with acacia gum to make a free flowing, granular powder. Milk thistle has traditionally been used for liver support and detoxification.1

Health Benefits

Milk thistle may have hepatoprotective (protecting liver), anticancer, anti-diabetic, and cardioprotective properties.1,2 Milk Thistle may protect the liver against damage from toxins and help prevent chronic liver diseases.1,2 Milk thistle may also reduce inflammation and play a role in stimulating the immune system (e.g., maintaining T cells).3 Milk Thistle may also reduce gastrointestinal symptoms of functional dyspepsia.4 Milk Thistle has been used historically for liver or gall bladder disorders,5 and it may aid in reducing tiredness and gastrointestinal upsets and boosting immune function in individuals with hepatitis C.6 Milk Thistle also may help reduce HbA1c (glycated hemoglobin), fasting blood glucose, blood lipid levels (e.g., total cholesterol, bad cholesterol (LDL cholesterol), and triglycerides) in diabetic patients.7


Patients with C282Y homozygous hemochromatosis should be cautious and consult a physician before supplementation of milk thistle.8


  1. Milk Thistle fruit. American Botanical Council. Accessed in July 2015.
  2. Tamayo C, Diamond S. Review of clinical trials evaluating safety and efficacy of milk thistle (Silybum marianum [L.] Gaertn.). Integr Cancer Ther. 2007 Jun;6(2):146-57. Review. PubMed PMID: 17548793.
  3. Post-White J, Ladas EJ, Kelly KM. Advances in the use of milk thistle (Silybum marianum). Integr Cancer Ther. 2007 Jun;6(2):104-9. Review. PubMed PMID: 17548789.
  4. Madisch A, Melderis H, Mayr G, Sassin I, Hotz J. [A plant extract and its modified preparation in functional dyspepsia. Results of a double-blind placebo controlled comparative study]. Z Gastroenterol. 2001 Jul;39(7):511-7. German. PubMed PMID: 11505331.
  5. Milk Thistle. MedlinePlus. NIH. Accessed in July 2015.
  6. White CP, Hirsch G, Patel S, Adams F, Peltekian KM. Complementary and alternative medicine use by patients chronically infected with hepatitis C virus. Can J Gastroenterol. 2007 Sep;21(9):589-95. PubMed PMID: 17853954; PubMed Central PMCID: PMC2657989.
  7. Huseini HF, Larijani B, Heshmat R, Fakhrzadeh H, Radjabipour B, Toliat T, Raza M. 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 Dec;20(12):1036-9. PubMed PMID: 17072885.
  8. Whittington C. Exacerbation of hemochromatosis by ingestion of milk thistle. Can Fam Physician. 2007 Oct;53(10):1671-3. PubMed PMID: 17934030; PubMed Central PMCID: PMC2231430.