Zinc May Harm Brain Development, Study Says

Zinc supplements given to infants in developing countries to improve growth and reduce susceptibility to infectious diseases could be harming the children’s mental development, British researchers reported in Saturday’s issue of the British journal The Lancet.

In a study of 188 children in Bangladesh, researchers from London’s Center for International Child Health found that babies whose mothers took zinc supplements during pregnancy had lower scores on mental and psychomotor tests than children whose mothers were given a placebo.

The researchers do not know how the supplements exert their effects. One theory suggests they could cause deficiencies in other micronutrients in the infants or may have a direct influence on brain development in the womb. Zinc deficiency is a problem in developing countries because diets are low in animal protein and high in fiber. Other supplements may be needed to counter zinc’s ill effects.