If your liver is in trouble, help may be as close as the produce section of the nearest market. It is avocado, otherwise known as alligator pear. Avocado (Persea americana) is not a vegetable, but a fruit with a leathery dark green skin that turns black when ripe. Avocado has a soft, smooth-tasting flesh and is eaten raw in salads or dips. The name "avocado" is the Spanish rendition of the Aztec word for "testicle." Perhaps coincidentally, avocado has long been deemed an aphrodisiac.

In folk medicine, avocado oil is also used to heal and soothe the skin. A condensed flavonol isolated from the seed has been reported to have antitumor activity in rodents. (But don't try this at home: the hard seeds may be quite toxic.) Many people shun avocados because they are 40 percent oil and therefore fattening. But eaten in moderation, they are a superior food. They are rich in vitamins E and C, fiber and potassium, and contain large amounts of folate, the vitamin best known for reducing the risk of birth defects in pregnant women. The vitamin D content of avocado oil exceeds that of butter or eggs. Including avocados in the diet lowers total cholesterol by 8 percent.

Recently, scientists in Japan fed 22 different fruits to rats whose livers had been experimentally damaged by a powerful toxin. The toxic damage was similar to that caused by viruses. Avocados were best at slowing the damage. Scientists believe that avocados may also be useful in treating viral hepatitis (a cause of liver cancer), as well as other sources of liver damage. The study measured changes in liver chemicals, called galactosamines, that mitigate the damage caused by the toxin. Enterprising scientists now plan to patent an avocado extract and then test it on humans.

While we eagerly await the avocado pill, there is something we can do. Eating avocados is a likely way of lending some protection to the liver. Since cancer frequently originates in or invades the liver, and this is also the chief organ of detoxification, it makes sense to include some avocado in your weekly dietary regimen.