Milk thistle
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Milk thistle is a prickly composite herb from the Mediterranean region and has been used extensively in traditional folk medicine to treat liver and gallbladder diseases. This traditional use has also been validated by modern clinical research. Milk thistle is also taken to shrink gallstones and remove bladder pain. If you want to use milk thistle to expel your gallstones, talk to your doctor first.

Improves Bile Acid Secretion

Preliminary clinical trials at New York University Langone Medical Center suggest that components of milk thistle, especially silymarin, protect against gallbladder stone formation. However, more research is necessary to draw firm conclusions. In animal models, milk thistle has shown significant stone dissolution by reducing cholesterol output in the bile and by expanding the bile acid pool. Bile acid dissolves free cholesterol in the bile, which is a key factor in cholesterol gallstone disease. Bile, a yellow or greenish fluid secreted by the liver, facilitates the absorption and digestion of fats in the small intestine.

Stimulates Gallbladder Contraction

Scientists at NYU Langone Medical Center reported that milk thistle reduces the risk of gallstones by stimulating more gallbladder contraction. This action of milk thistle, however, carries a risk of serious complication. Sometimes, gallstones come loose and lodge in the bile ducts between the liver and the intestine. This biliary obstruction inhibits the flow of bile, causing severe pain, gallbladder inflammation and jaundice. Make sure you use milk thistle or any other herbal supplements properly under a doctor’s care.

Therapeutic Dosages

Studies vary in the dosage of milk thistle used. According to the University of California-San Diego, a reasonable therapeutic dosage might be about 420 mg to 500 mg of a standardized milk thistle extract per day. Silymarin bound to phosphatidylcholine, a milk thistle supplement, tends to be better absorbed by the body than other preparations. When taking this form, limit your intake to less than 400 mg per day.


Milk thistle has no reported side effects. It is safe for most adults when used in moderate amounts. Investigators from the University of California-San Diego have felt comfortable giving milk thistle to pregnant and nursing women. In one case report, an old Australian woman using a milk thistle extract was found to have several episodes of nausea, vomiting, abdominal cramps and weakness.