Silymarin is the flavonoid complex that can be extracted from the seeds of the milk thistle plant (Silybum marianum), and the terms “milk thistle” and “silymarin” are often used interchangeably. Milk thistle has been used medicinally for more than 2,000 years, and its most common uses are for treatment of liver and gallbladder disorders. The dried seeds from milk thistle extract contain about 60 percent silymarin, and silymarin itself contains a mixture of silibinin, silychristin, and silydianin. The most dominant is silibinin, which accounts for about 50 to 60 percent of the silymarin. Silibinin is also the most biologically active as an antioxidant and for its ability to protect the liver and cells.
In the lab, researchers have shown that silymarin can kill prostate cancer cells (Zi 1999) and in some cases, “convert” them into acting like healthy cells again. More recent studies, again in the lab, have shown that silibinin can inhibit the invasion, motility, and migration of prostate cancer cells. (Wu 2009)
In a University of Colorado study, scientists explored the impact of dietary silibinin in male mice that had prostate tumors. One group of mice served as controls while other mice were fed the supplement for 11 weeks. Dietary silibinin inhibited the growth of the prostate tumors by as much as 60 percent as well as suppressed progression of the tumors. Silibinin also inhibited the tumors from invading the seminal vesicle by up to 81 percent and also induced apoptosis (cell suicide). (Singh 2008)
Silymarin has also demonstrated anticancer activity against xenografts of human prostate cancer cells. In a study conducted in the Czech Republic, researchers enrolled 37 men who had recently undergone radical prostatectomy in a double-blind, placebo-controlled trial. For six months, half the men took 570 mg of silymarin and 240 micrograms of selenium and the other half took placebo. At the end of the six months, men who had taken silymarin and selenium had improved quality of life scores and significant reductions in two markers of lipid metabolism known to be associated with the progression of prostate cancer, low-density lipoprotein and total cholesterol. study properties. (Vidlar 2010)
Consult a knowledgeable healthcare provider to determine the best dose of silymarin for your needs. No specific dosage has been identified for prostate health. Taking more than 1,500 mg daily can cause a laxative effect. Side effects are generally mild and usually involve the gastrointestinal tract (e.g., nausea, gas, diarrhea, indigestion).
Singh RP et al. Silibinin inhibits established prostate tumor growth, progression, invasion, and metastasis and suppresses tumor angiogenesis and epithelial-mesenchymal transition in transgenic adenocarcinoma of the mouse prostate model mice. Clin Cancer Res 2008 Dec; 1:14(23): 7773-80
Vidlar A et al. The safety and efficacy of a silymarin and selenium combination in men after radical prostatectomy—a six month placebo-controlled double-blind clinical trial. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2010 Sep; 154(3): 239-44
Wu K et al. Silibinin reverses epithelial-to-mesenchymal transition in metastatic prostate cancer cells by targeting transcription factors. Oncol Rep I 2010 Jun; 23(6): 1545-52