March 9, 2007
The heart needs copper
Although too much copper can be problematic health-wise, researchers at the University of Louisville in Kentucky and the USDA Human Nutrition Research Center reported online on the March 5, 2007 in The Journal of Experimental Medicine that supplementing mice with the mineral prevents enlargement of the heart when the organ is stressed. Deficient copper intake has been associated with increased cholesterol levels, clot formation, and heart disease.
Y. James Kang and colleagues at the University of Louisville School of Medicine used a mouse model of hypertrophic cardiomyopathy caused by pressure overload induced by constriction of the ascending aorta. A group of control mice received sham surgeries. The animals received a diet providing RDA adequate levels (6 milligrams per kilogram diet) of copper for eight weeks. After four weeks on the diet, some of the animals were changed to a diet providing higher levels (20 milligrams per kilogram diet) for the remaining four weeks.
Four weeks after the surgery, cardiac hypertrophy (enlargement) was observed. This was significantly reversed during the final four weeks of the study in the animals who received the higher copper diet, while the remainder went on to develop heart failure. The researchers found that supplementing with copper promoted the synthesis of vascular endothelial growth factor (VEGF), a protein that increases the growth of new blood vessels, which was reduced in the late phase of cardiac hypertrophy among mice that did not receive extra copper.
The human equivalent dose for the high dose of copper used in the study is 2.9 milligrams per day, however, the recommended daily intake is only 0.9 milligrams. "Should similar effects of copper supplementation be found in controlled studies in human patients," the authors write, "this will point the way to a simple, nontoxic and extraordinarily economical therapy for hypertrophic cardiomyopathy."