Low ferritin does not necessarily mean thalassemia. 1. Thalassemia is thalassemia, which does not necessarily cause low ferritin, but sometimes elevated ferritin. If hemolysis occurs in thalassemia patients, the iron in the red blood cells will enter the blood plasma, resulting in high iron values, ferritin will also rise accordingly. 2. Low ferritin indicates that the body does not have enough iron reserves, which is common in iron deficiency anemia. Lower ferritin is also seen in massive blood loss, chronic diarrhea, malnutrition and other diseases. Therefore, low ferritin is not necessarily thalassemia, but probably iron deficiency anemia. If the test results show low ferritin, it is recommended to consult a doctor in time to clarify the cause of the disease with the help of a doctor and carry out targeted treatment.