A new animal study adds to evidence
that including foods rich in copper, along with a well-balanced diet, may be
good for an ailing heart. The study appears in the March 19 issue of the
Journal of Experimental Medicine.
Retired physiologist Jack Saari participated in the study while with the
Agricultural Research Service (ARS)
Grand
Forks Human Nutrition Research Center in North Dakota. Lead author Y. James
Kang conducted the study at the
University
of Louisville Medical Center in Kentucky.
Copper is an essential trace element that acts as a cofactor for the
physiological function of many proteins. Tiny amounts are contained in hundreds
of copper-dependent proteins that perform essential biological functions in
animals and humans.
Hypertrophy is an increase in the size of a tissue or organ. For the study,
the researchers challenged two groups of mice for two months, resulting in
cardiac hypertrophy—a condition in which the heart becomes bigger followed
by disease. Enlarged hearts often occur in response to elevated blood pressure.
Both groups were fed the equivalent of the recommended dietary amount of
copper for adults for the entire two months. But after the first month, the
test group's diet was increased to contain the equivalent of three times the
human recommended amount of dietary copper—an amount that was still just
one-third of the equivalent safe upper limit for humans.
By four weeks, heart disease developed in all the mice, and by eight weeks,
heart failure developed in the control mice. But the hearts of the mice
receiving the extra copper returned to normal size and function, despite the
fact that the cardiac challenge continued throughout the eight-week period.
In human hypertrophic heart disease, enlarged heart muscle leads to
shortness of breath during exertion, discomfort caused by reduced blood supply
to the heart muscle and/or abnormal heart rhythms.
Confirmational, controlled human research studies are needed in which
volunteers with hypertrophic heart disease consume copper-rich diets. But this
mouse study suggests that consuming more copper in the diet may help people
with hypertrophic, or thickened, heart muscle conditions.
For a list of foods that are good sources of copper, go to
www.nal.usda.gov/fnic/foodcomp/Data/SR17/wtrank/wt_rank.html
and click on "copper." The list will sort foods in descending order
by copper content in terms of common household measures.
ARS is the U.S. Department of
Agriculture's chief scientific research agency.
