They include cognitive development, immune function, work performance or adverse pregnancy outcomes. Several studies have been conducted and published demonstrating the effect of ID and IDA on psychomotor development and performance. During infancy studies have shown that IDA is related to decrease in responsiveness and activity, and tendency to fatigue. This is due to the increased iron absorption among iron deficient subjects, what facilitates the absorption of other metals.
Lead poisoning is relevant especially during infancy because it also affects cognitive functions.