Milk thistle (Silybum marianum), from the family Asteraceae, is also known as St. Mary's or Our Lady's thistle. Its stems are 30-150 cm when erect and its leaves are large, prickly, and glossy, with milk-white veins. The thistle-like, violet-purple flowers are 5 cm long and surrounded by long spiny appendages. The fruits of this plant are blackish and specked. Milk thistle is found in dry, rocky, and stony soils, and is native to the Mediterranean region of Europe.

The bioflavonoid compound, silymarin, derived from milk thistle, increases protein synthesis in liver cells, which accelerates the regeneration and production of these cells. Silymarin in milk thistle extract also induces an alteration of liver cellular membranes to stop absorption of a variety of toxins (by binding to the outside of liver cells), including the phalloidine and amantine toxins of the lethal Amanita phalloides mushroom. Milk thistle has also been known to prevent formation of prostaglandins and inhibit lipoxygenase from forming leucotrienes (polyunsaturated fatty acids) in the liver.

Silymarin and its main component, silybin, function as antioxidants, protecting cell membranes from free-radical mediated oxidative damage, known as lipid peroxidation. This is useful against those toxins such as alcohol and carbon tetrachloride, that produce their damaging effects by free radical mechanisms. Silymarin also increases the activity of the antioxidant SOD in red blood cells and lymphocytes, demonstrated in patients suffering from chronic alcoholic liver disease.


in animals: when silymarin was given before poisoning with Amanita mushrooms, toxicity was 100% prevented

-if given within ten minutes of exposure to mushroom, silymarin was also 100% effective

-when given within 24 hours of exposure, death was prevented and the amount of liver damage was reduced

in humans: silymarin has been used to treat hepatic disorders-after three months of therapy with silymarin, chronic hepatitis improved

in humans: when 420 mg of of silymarin was used daily for 6-36 months in patients with cirrhosis of the liver, 10 of 20 improved and 4 deteriorated

in humans: 2 groups of patients receiving psychotropic drugs as long term therapy- IA was treated with psychotropic drugs and silymarin IB was treated with silymarin with suspension of psychotropic drugs. Result:treatment with silymarin reduces lipoperoxidative hepatic damage caused by chronic use of phenothiazines and butyrophenones. The effect of silymarin is greater when treatment with psychotropic drugs is suspended.

Other Benefits of Milk Thistle


  • prevention of plaque buildup
  • prevention of hardening of arteries
  • treating cholangitis(inflammation of the bile ducts)
  • treating cholestosis of pregnancy(suppression of the flow of the bile)
  • treating peri-cholangitis(inflammation of tissues surrounding the bile ducts
  • treating psoriasis (skin disease)
  • the seed are also helpful for disorders of the spleen and gallbladder

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