Folic Acid

Folic Acid in depth

What it is

Folic acid is the synthetic form of folate, also known as vitamin B9. The body uses folate to make DNA and to form new cells. Public health guidance in many countries advises women who could become pregnant to make sure they get enough folate.

Forms you may see on a label

Folate is the natural form found in food. Folic acid is the form used in most supplements and in fortified foods because it is stable and well absorbed. Some supplements use other forms, such as 5-methyltetrahydrofolate (methylfolate). The label shows which form is used. Amounts are often expressed as dietary folate equivalents (DFE).

Where it occurs naturally

Dark green leafy vegetables, pulses such as dals and chickpeas, and citrus fruit are good natural sources. In some countries flour and breakfast cereals are fortified with folic acid.

Safety notes and who should check first

The recommended intake is 400 mcg DFE a day for adults and 600 mcg DFE during pregnancy. The Tolerable Upper Intake Level for folic acid from supplements and fortified foods is 1,000 mcg a day for adults. It does not apply to folate naturally in food.

Large amounts of folic acid can correct the anaemia caused by vitamin B12 deficiency without correcting the nerve damage, so a low B12 level can go unnoticed. Folic acid can also interact with some medicines, including methotrexate and some anti-seizure medicines, so ask a doctor or pharmacist first if you take them.

Source: NIH Office of Dietary Supplements: Folate fact sheet

Reference information last updated 9 November 2026. It is general education and not medical advice.