PORTLAND, OREGON. Extracts from milk thistle (Silybum marianum) have been used in herbal medicine for 2000 years. Pliney The Elder (AD 23-79) reported that a mixture of the plant's juice and honey was excellent for "carrying off bile". Since then many scientists have lauded milk thistle's ability to treat liver disease. Since 1969 milk thistle extracts have become very popular and now account for sales of $160 million a year in Germany alone. Researchers at the Oregon Health Sciences University recently released a major report reviewing the scientific papers dealing with silymarin, the active ingredient in milk thistle extracts. A standard silymarin extract contains 70 per cent silymarin which in itself is a mixture of flavonolignans, silydianin, silychristine, and silybin. Silybin is believed to be the most biologically active component and is rapidly absorbed into the blood stream and bile after an oral dose. Silybin acts as an antioxidant, decreases the activity of tumor promotors, and acts as a mild chelator of iron. Studies have shown that silymarin is beneficial in the treatment of acute viral hepatitis and some toxin and drug-induced forms of hepatitis. There are also reports that silymarin is effective in the treatment of alcoholic liver disease and chronic hepatitis. Therapeutic dosages range from 140 mg twice a day to 560 mg/day for periods from six months to six years. No adverse side effects of silymarin have been documented and the researchers conclude that well-designed, double-blind, placebo-controlled studies should be carried out to further investigate silymarin's benefits in the treatment of a variety of diseases.
Flora, Kenneth, et al. Milk thistle (Silybum marianum) for the therapy of liver disease. American Journal of Gastroenterology, Vol. 93, February 1998, pp. 139- 43