He has not yet treated me. Fixed in the public's mind is the idea all anemia results from iron deficiency. An anemia is a low number of red blood cells. People with anemia, regardless of cause, feel dragged out because the diminished population of blood cells cannot supply the body with the oxygen it needs. Red blood cells are trucks that transport oxygen from lungs to all body organs tissues.
Iron deficiency is a common cause of anemia.
If that is the case, the next step is finding the reason for the iron deficiency. Bleeding is often the cause of iron-deficiency anemia. Blood is the largest depository for iron. The bleeding can be internal and not obvious to the patient. However, there are other reasons why anemias develop.