Macrocytic anemia, neural tube malformation, hyperhomocysteinemia and other clinical manifestations may occur in the absence of folic acid. 1. Megaloblastic anemia: patients generally have pale yellow skin color, pale lips, eyelids and conjunctiva, nail beds, and a few may have jaundice; yellow, fine, dry and sparse hair, enlarged liver and spleen. There is often loss of appetite, abdominal distension, diarrhea and lingual inflammation; lingual inflammation is the most prominent, with red tongue, atrophied tongue papilla, smooth surface, commonly known as “beef tongue”, accompanied by pain. 2. Neural tube malformation: Folic acid deficiency during pregnancy, especially in the early stage, can cause fetal spina bifida, cerebrospinal bulge, anencephaly and so on. 3. Hyperhomocysteinemia: this disease is mainly manifested by skeletal abnormalities (osteoporosis, scoliosis, etc.), lens dislocation (or with glaucoma, retinal detachment), mental retardation, behavioral disorders, convulsions and so on.