Chance of Colon Cancer Connected to Copper Consumption
By Judy McBride
February 26, 2001
Take some oysters, liver, nuts and
seeds, wash them down with a little cocoa, and top them off with a chocolate
bar for dessert. While this combination may not appeal to your taste buds,
including these foods in a well-balanced diet may reduce your risk of colon
cancer, according to recent animal studies by
Agricultural Research Service
These foods are all high in copper--an essential trace element that is below
the new recommended intake (0.9 milligram per day) in about one-quarter of U.S.
Studies of mice and rats--led by ARS nutritionist
Cindy D. Davis
at the Grand Forks, N.D., Human
Nutrition Research Center--add to evidence that a low-copper diet
significantly increases risk of colon cancer. Copper joins selenium, calcium,
carotenoids and fiber as being important for a healthy colon.
Colon cancer is the second leading cause of cancer mortality in the United
States and the fourth worldwide. Diet is thought to be the single greatest
contributor to colon cancer in humans, possibly accounting for 35-45 percent of
the disease risk.
Davis and colleagues found that rats raised on only one-fifth of their
copper requirement had significantly more precancerous lesions in their colons
than the animals that got adequate copper after both groups were given a
cancer-causing chemical. And copper-deficient colon cells showed enzyme
abnormalities that have been reported in precancerous lesions in both humans
Davis also looked for a copper connection in mice with a genetic
predisposition to develop intestinal tumors. Since the mouse mutation is
similar to one found in some human families, these animals make a good model
for testing the effects of dietary changes. Not surprisingly, the mice fed the
copper-deficient diet had significantly more and bigger tumors than the animals
fed adequate copper.
Earlier this month, ARS honored Davis as the "outstanding early career
research scientist of 2000" (link to news
release). ARS is the U.S. Department of
Agricultures chief scientific research agency.
Scientific contact: Cindy D. Davis, ARS
Grand Forks Human Nutrition Research
Center, Grand Forks, N.D., phone (701) 795-8380, fax (701) 795-8220,