Iron deficiency is regrettably a common mineral deficiency of early childhood.
Symptoms include poor appetite, weight loss, irritability, increased susceptibility to infections, and finally, anemia and pale appearance. Since the first four symptoms are rather nonspecific and common to many kids in the 15-18 month age range anyway, the diagnosis is often missed early on. Anemia doesn't occur until the total body store of iron is quite low, since carrying oxygen to the tissues is the top priority of all. It is now thought that the more severe cases of iron deficiency may suffer permanent brain injury with loss of ultimate IQ points, so this is not a trivial issue. Iron deficiency is unusual in full term first born children , in breast fed infants especially if supplemented with iron, or in children fed iron-fortified formula.