What is folic acid? Folic acid (folate) is a vitamin and is needed to make new cells in the body. Pregnant women in particular need a good supply of folic acid, which is used by the developing baby. The very early stages of pregnancy are crucial in the need for folic acid. This is why folic acid supplements are recommended for women planning a pregnancy. Many foods contain folic acid, including vegetables such as spinach, sprouts, broccoli, green beans, and potatoes.