American Chemical Society
Avocados contain potent liver protectants
HONOLULU, Dec. 18 - Researchers in Japan have discovered that avocados contain potent chemicals that may reduce liver
damage. The finding could lead to the development of new drugs to treat liver disease, the researchers say. They presented their findings today during the 2000 International Chemical Congress of Pacific
The weeklong scientific meeting, held once every five years, is hosted by the American Chemical Society, in conjunction with its counterparts in Australia, Canada, Japan and New
To evaluate the protective activity of food against liver injury, the researchers fed 22 different fruits to a group of rats with liver damage caused by galactosamine, a powerful liver
toxin. As measured by changes in the levels of specific liver enzymes, the avocado showed the most potent activity among these fruits in slowing liver damage, according to the lead researchers, Hirokazu
Kawagishi, Ph.D., and Kimio Sugiyama, Ph.D., professors at Shizuoka University in Shizuoka, Japan.
"Besides offering taste and nutrition, avocados seem to improve liver health," says
Kawagishi. "People should eat more of them."
Five compounds appear to be active in reducing liver damage. Each was tested in rats with chemically induced liver injuries. The injuries
resembled those caused by viruses, suggesting that avocado extracts may be especially promising for the treatment of viral hepatitis, according to the researchers.
The investigators do not know
whether the results from the rat studies will translate into liver protection among humans, how much avocado extract it will take to have a beneficial effect, or how the active chemicals work. Further
studies are needed, they say.
The leading producer of avocados worldwide is Mexico. In the United States, California is the leader, followed by Florida and Hawaii.
The study adds to a
growing body of evidence supporting the many health benefits of the avocado, a popular addition to salads, sandwiches and California rolls. In addition to benefiting the liver, the green-skinned fruits
are rich in vitamins E and C, high in fiber and potassium, and contain large amounts of folate, a vitamin that helps reduce birth defects in pregnant women.
While avocados are high in fat, much
of the fat is of the monounsaturated variety, which has been shown to reduce cholesterol levels.
The study was funded by Monbu-syo (the Ministry of Education in Japan) and by Kagome Co., Ltd., a
major food and beverage manufacturer in Japan. Kagome plans to patent the avocado extract and test it on humans in the near future, the researchers say.
More than 8,000 research papers will be
presented during this year's International Chemical Congress, which is sponsored jointly by the American Chemical Society, the Chemical Society of Japan, the Canadian Society of Chemistry, the Royal
Australian Chemical Institute and the New Zealand Institute of Chemistry.
The poster on this research, ORGN 1285, will be presented at 9 a.m., Monday, Dec. 18, at the Hilton Hawaiian Village,
Coral Ballroom III, Mid-Pacific Conference Center, during the symposium, "Natural Products of Chemistry: Biological Activity and Synthesis."
Hirokazu Kawagishi and Kimio Sugiyama are
both professors in the department of applied biological chemistry at Shizuoka University in Shizuoka, Japan.