Zinc is a mineral that is often found to be deficient in children with symptoms of ADHD. Zinc deficiency may affect cognitive development by alterations in attention, activity, neuropsychological behaviour and motor development. Zinc and copper levels must be in balance and have shown to correlate to ADHD symptoms when the ratio is low. Studies have shown that when children are supplemented with zinc, it decreases hyperactive, impulsivity and poor socialization behaviours.