Milk thistle: your liver is your body's detox center. Keeping it healthy is the key reason to reach for this herb.

AKA: Silybum marianum, St. Mary's thistle, blessed milk thistle PARTS USED: Seeds, fruits

WHAT IT DOES BEST: Milk thistle is increasingly used to promote general health and efficient detoxification, to protect against environmental pollutants and to reduce the toxic side effects of drugs used in chemotherapy. Traditionally considered a liver tonic, milk thistle is used in Europe for chronic hepatitis and cirrhosis (liver malfunction). Clinical studies suggest that standardized milk thistle seed extract may also protect against liver damage from exposure to hazardous chemicals.

WHAT'S THE ACTIVE INGREDIENT? Silymarin, which is composed of a group of plant compounds (known as flavolignans) that protect and restore the liver. Silymarin stimulates production of the body's own primary antioxidant, glutathione. Glutathione is responsible for deactivating and eliminating a wide variety of toxins, drugs, hormones and chemicals from the body. It is produced primarily in the liver, but when there is disease or inflammation, glutathione production is reduced. Many common drugs, such as acetaminophen, also deplete glutathione levels.

Silymarin appears to work in two ways: first, by keeping toxins out of liver cells; and second, by stimulating production of healthy new liver cells.

RECENT FINDINGS: A review published in the 2001 issue of Drugs concluded that silymarin significantly reduced liver-related deaths from cirrhosis. Silymarin also reduced the amount of insulin required by people suffering from cirrhosis-related diabetes.

Preliminary studies suggest that milk thistle may have anticancer effects. This is attributed to the strong antioxidant action of silymarin. Researchers are also examining whether milk thistle may both prevent the toxic side effects of some cancer treatments (cyclosporine ...