WEDNESDAY, March 7, 2007 (HealthDay News) -- Got copper? Your heart might thank you, a new study suggests.
In research involving mice, copper supplements restored normal cardiac function in rodents with enlarged hearts, otherwise known as hypertrophy.
"If you don't get treatment for it, the heart stops functioning properly," said lead researcher Y. James Kang, professor of medicine and pharmacology at the University of Louisville, in Kentucky.
But adding copper to the animals' diets reversed the overgrowth of their hearts, the researchers reported. They attributed the beneficial effects to increased production of cardiac blood vessels and to improved function of vascular endothelial growth factor, a molecule involved in function of the delicate lining of those blood vessels.
The team reported its findings in the Journal of Experimental Medicine.
"We intend to study this in human patients," Kang said. "In people with heart failure, we will look at blood copper levels and see if supplements have an effect."
Not everyone is convinced the controversial treatment will work, however. "I'm not sure that it is really well accepted," said William Johnson, a research chemist at the U.S. Department of Agriculture's Grand Forks Human Nutrition Research Center.
The U.S. Recommended Dietary Allowance for copper is 0.9 milligrams a day. U.S. Department of Agriculture (USDA) surveys have found an average intake of 1.6 milligrams a day for men ages 19 to 60 and 1 milligram a day for women in that age group.
Supplements aren't the best way to get an adequate amount of copper, said Dr. Leslie M. Klevay, an unabashed copper enthusiast who trained Yang while at the Department of Agriculture and is now professor of internal medicine at the University of North Dakota. He has been studying the effects of copper on the heart for a decade.
Supplements don't work well, Klevay said, because the copper they contain is in a form that is not well absorbed by the body. He recommends supplements containing iron, because they help put dietary copper to work. Good food sources of copper include grains and nuts, Klevay said. "Liver is the best, and peanut butter is terrific," he added.
The first evidence that suggested copper might be important for the heart came about 75 years go with reports of animal illnesses such as "falling disease," in which Australian cows simply keeled over and died because of a copper deficiency, Klevay said.
He picked up on the subject and began a series of studies that continue today. "We first experimentally raised cholesterol in rats by making them copper-deficient," Klevay said. "Then, we did the same in people. Four or five papers preceding this one have shown that the adverse effects of copper deficiency on the heart are reversible."
Klevay goes against the prevailing medical wisdom by proclaiming that "the idea that fat has something to do with heart disease is dead -- heart disease is a problem of deficiency." He acknowledged that hard evidence to that effect is not available, however.
"There have been no long-term supplement trials," Klevay said. Nevertheless, he said, "clearly, if fat is obsolete, there should be emphasis on other therapies."
For his part, Johnson said it's not clear how copper might help hypertrophic hearts.
"It looks like they might be activating some kind of cardiac stem cell," Johnson said of the Kang report. "They have been involved with this center on copper and heart disease. The work is new, and I don't know how it will be accepted in science," he added.
Find out more about cardiac hypertrophy at the American Heart Association.