Ferritin 340 μg/L suggests that it is higher than the normal reference range and may be associated with increased body iron storage, increased ferritin synthesis, anemia, and increased tissue release. 1. Increased iron storage in the body. Normal ferritin reference values range from 15 to 200 μg/L in men and from 12 to 150 μg/L in women. When the ferritin is 340 μg/L, it is high, which may be related to the increase of iron storage in the body caused by primary hemochromatosis, secondary iron overload, and so on. 2. Increased synthesis of ferritin. When the body has inflammation, tumor, hyperthyroidism, etc., it can cause increased ferritin synthesis, resulting in high ferritin. 3. Anemia. When the body has aplastic anemia, hemolytic anemia, etc., resulting in the lack of blood in the body, feedback causes ferritin to be elevated. 4. Increased tissue release. When the body suffers from chronic liver disease, liver necrosis, etc. can lead to increased release of ferritin. When the body ferritin is elevated, the cause needs to be clarified and actively treated under the guidance of the doctor.