Simple small cell anemia is most commonly associated with small cell hypochromic anemia, or iron deficiency anemia. The most common causes are as follows: 1, women of childbearing age with heavy menstruation cause, blood loss, i.e. iron loss, causing iron deficiency anemia; 2, bleeding from the gastrointestinal tract, such as small amount of long-term bleeding from gastric ulcer, also causes small cell anemia; 3, gastrointestinal malignant tumors cause long-term, continuous blood loss from the gastrointestinal tract, causing small cell anemia. Small cell anemia is firstly caused by removing the cause, for example, if women of childbearing age have heavy menstruation, they should adjust their menstrual cycle and menstrual volume, and if they do not have heavy menstruation, they can recover quickly through iron supplementation. If it is a gastrointestinal disease, such as ulcer disease, the ulcer disease should be treated. If a gastrointestinal tumor causes it, treat the tumor, and these microcytic anemias can be controlled. Patients with microcytic anemia have no bone marrow problems and are caused by blood and iron loss, so they can recover quickly in most cases if the causative factors are removed and iron is supplemented.