Thalassemia is a group of genetically inherited blood diseases that affect the body's ability to produce hemoglobin, the protein in red blood cells that carries oxygen. This condition is most common in people of Italian, Greek, Middle Eastern, Southern Asian and African ancestry. It is passed to children by parents who each carry the mutated thalassemia gene. The National Human Genome Research Institute has more on its "Learning About Thalassemia" page.
There are two types of thalassemia, alpha and beta. The difference is in which part of the oxygen carrying protein in red blood cells is missing. Most individuals with alpha-thalassemia have a mild form of the disease, with varying degrees of anemia. In its most severe form, alpha-thalassemia, results in fetal or newborn death. Beta-thalassemia is generally mild.
At its most severe, beta-thalassemia is called Cooley's anemia and requires frequent transfusions and close medical monitoring. Mild thalassemia, which appears to be the condition that affects your daughter, can cause mild anemia and often has few or no symptoms, although it certainly can make you feel tired. Blood tests can distinguish between iron deficiency and thalassemia as the cause of anemia. When thalassemia is the cause, taking iron supplements or eating iron-rich foods won't help.
Probably, no treatment is needed in your daughter's case.
Andrew Weil, M.D.