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A Deficiency Made Me Do It

Presents a study by Dr. William Walsh of Illinois Institute regarding the effect of nutritional imbalances. Relationship of zinc deficiency and violent behavior in men; Role of zinc in brain function; List of zinc-rich foods.

The nature-versus-nurture debate has long raged over the origin of violentbehavior: is it in the genes, or in the upbringing? William Walsh, Ph.D., and his colleagues at the Health Research Institute in Illinois think they have a third possibility: it's in the body, in the form of nutritional imbalances.

In a study published in Physiology and Behavior, Walsh compared the results of blood tests given to 135 assaultive men to those of 18 controls with no history of violence. It turned out that the violent males had lower zinc and higher copper levels than the controls, and that the more imbalanced the ratio, the more severe and more frequent were their aggressive outbursts.

Walsh's colleague, Ronald Isaacson, Ph.D., says that while its relationship to violent behavior is unclear, "zinc plays an important role in brain function, and thus in mental well-being." (High levels of copper have also been linked to hyperactivity and schizophrenia.) Of course, says Isaacson, "the causes of assaultive behavior are much more complicated than blood copper and zinc"; not only may societal and familial influences be involved, but perhaps other chemical imbalances as well. Still, when the young men were treated for their zinc deficiency and copper overload, their assaultive episodes declined substantially.

These subjects were treated with therapeutic doses of vitamin and mineral supplements, since "diet by itself will not effect the changes that are needed in these individuals," says Isaacson. Though such severe imbalances are rare, Isaacson notes that Americans' diets are generally low in zinc--in part he says, because we eat so many processed foods. Even the pacifists among us may benefit from a diet that includes zinc-rich meat, milk, eggs, legumes (such as peanuts), and whole grain breads and cereals.