Hemoglobin is a pigment protein that is mainly found in the red blood cells of the human body. Hemoglobin has important physiological functions, it can play the function of transporting oxygen and transporting carbon dioxide, but the synthesis process of hemoglobin is very complex and requires various raw materials, among which the basic raw materials for synthesizing hemoglobin include iron, folic acid, vitamin B12 and protein, and the deficiency of any one of the hematopoietic raw materials will cause anemia. In clinical practice, if iron is deficient, red blood cells cannot use iron to synthesize hemoglobin normally, and the patient will have symptoms of iron deficiency anemia, which manifests as pallor, dizziness and weakness. By the same token, if folic acid and vitamin B12 are deficient, it will cause megaloblastic anemia, and the patient will have obvious symptoms of peripheral neuritis such as loss of appetite and numbness of the extremities in addition to anemia symptoms. If protein is deficient, it also tends to cause anemia. Therefore, the basic raw materials for synthesizing hemoglobin are iron, folic acid, vitamin B12, and protein.