The main role of folic acid is that it can prevent anemia, fetal congenital malformations, neural tube defects, and lower blood pressure. 1. Prevent anemia: folic acid and vitamin B12 are jointly involved in the growth and maturation of red blood cells, oral folic acid can prevent and treat megaloblastic anemia; pregnant women also need to take folic acid to produce normal red blood cells and improve the symptoms of anemia during pregnancy. 2. Prevent fetal congenital malformations: Fetuses are prone to congenital malformations during growth and development, so you can take folic acid to reduce the risk of your baby being born with defects, and also prevent fetal congenital heart disease and so on. 3. Neural tube defects: women need to take folic acid one month before conception or in the first trimester of pregnancy, which can prevent fetal neural tube defects. 4. Lower blood pressure: high blood pressure is associated with high levels of homocysteine in the serum, and taking folic acid at this time can lower the level of homocysteine in the serum, thus treating high blood pressure. Folic acid should be taken under the guidance of a doctor.