London: Iron deficiency is a condition resulting from too little iron in the body. Iron deficiency is the most common nutritional deficiency and the leading cause of anemia in the world. In the USA, despite food fortification, iron deficiency is on the rise in certain populations.
Iron deficiency at critical times of growth and development can result in premature births, low birth weight babies, delayed growth and development, delayed normal infant activity and movement.
Iron deficiency can be the result of numerous and multiple causes. These fall into two broad categories: an increased need for iron and/or decreased intake or absorption of iron. Lower IQs have been linked to iron deficiency occurring during critical periods of growth. source