Agricultural Research Service (ARS) scientists now have described how adequate amounts of copper are important to brain function. Their animal model studies suggest that levels of copper intake are critical to the fetus during pregnancy—a concept called "nutritional programming."

An early animal study led by biologist Curtiss Hunt showed that even moderate copper deprivation in pregnant rats led to underdevelopment of memory-control areas of their pups' developing brains. He is a lead scientist at the ARS Grand Forks Human Nutrition Research Center (GFHNRC) in Grand Forks, N.D.

The study rats were fed low-copper diets during gestation, lactation, or both. Their pups—when compared to pups born to mothers fed copper-sufficient diets—exhibited slowed development of the dentate gyrus and hippocampal areas of their brains. These areas are important for higher brain functions, such as learning.

Several biochemical mechanisms that underlie impaired brain development associated with copper deficiency have now been described in Nutritional Neuroscience, a book co-authored by GFHNRC chemist W. Thomas Johnson.

Generally, copper deficiency is not a public health concern in the United States. But 8 to 16 percent of childbearing-age women were found to have inadequate copper intakes, according to ARS national food-intake survey data from 2001 and 2002.

Eating a balanced diet containing a variety of nutritious foods is the best approach to getting adequate dietary copper, according to Johnson. Good sources of copper include beef liver, mushrooms, trail mix, barley and canned tomato puree.

Read more about this research in the September 2007 issue of Agricultural Research magazine.

ARS is the U.S. Department of Agriculture's chief scientific research agency.