Milk thistle is native to the Mediterranean region. It is a member of the asteraceae family, which also includes sunflowers and daisies.Milk thistle gets its name from the milky white sap that comes from the leaves when they are crushed. The flowers are red purple. The small, hard-skinned fruit is brown, spotted, and shiny. Milk thistle spreads quickly (it is considered a weed in some parts of the world), and it matures in less than a year.
What’s It Made Of?
The active ingredient -the one that protects the liver -in milk thistle is known as silymarin, a chemical extracted from the seeds. Silymarin is actually a group of flavonoids (silibinin, silidianin, and silicristin), which are thought to help repair liver cells damaged by alcohol and other toxic substances. Silymarin also protects new liver cells from being destroyed by these same toxins. It reduces inflammation (which is why it is often suggested for people with liver inflammation or hepatitis) and is a strong antioxidant.
Most milk thistle products are standardized preparations made from the seeds of the plant, to contain 70 to 80% of silymarin.
Milk thistle has been used for 2,000 years as an herbal remedy for a variety of ailments, particularly liver, kidney, and gall bladder problems. Several scientific studies suggest that substances in milk thistle (especially a flavonoid called silymarin) protect the liver from toxins, including certain drugs, such as acetaminophen (Tylenol), which can cause liver damage in high doses.
Liver disease from alcohol
Milk thistle is often suggested as a treatment for alcoholic hepatitis and alcoholic cirrhosis. But scientific studies show mixed results. Most studies show milk thistle improves liver function and increases survival in people with cirrhosis or chronic hepatitis.
Based on traditional use, milk thistle has been used as an emergency antidote for poisoning by death cap mushroom (Amanita phalloides). Animal studies have found that milk thistle extract completely counteracts the toxic effects of the mushroom when given within 10 minutes of ingestion. If given within 24 hours, it significantly reduces the risk of liver damage and death.
Early laboratory studies suggest that silymarin and other active substances in milk thistle may have anti-cancer effects. These substances appear to:
- Stop cancer cells from dividing and reproducing
- Shorten the lifespan of cancer cells
- Reduce blood supply to tumors
Some studies suggest silymarin may favorably supplement sunscreen protection and may help reduce the risk of skin cancer. Other studies suggest milk thistle acts synergistically with chemotherapy. More studies are needed to show whether milk thistle has any effects in the body (not just in test tubes).
Milk thistle is widely used in the treatment of viral hepatitis (particularly hepatitis C). However, studies show mixed results. Some studies found improvements in liver function, while others did not. In one study of 16 patients who didn’t respond to interferon and ribavirin therapy, milk thistle significantly reduced the viral load of hepatitis C. In 7 of the subjects the virus decreased to undetectable levels after 14 days of therapy.
What are the Side Effects of Milk Thistle?
One of the best things about milk thistle is its gentle nature. Compared to many other supplements and herbal remedies that bring with them side effects such as headaches, virtually all parts of the milk thistle plant have been used with no reports of toxicity. Adverse effects in clinical and lab studies related specifically to the seed extract (silymarin) are also virtually nonexistent, although it may have a mild and short-lived laxative effect for some people.