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Common questions about folic acid

How does folic acid work?

In anaemia

Folic acid helps make healthy red blood cells, which carry oxygen around the body.

If you do not have enough folic acid, your body can make abnormally large red blood cells that do not work properly.

This causes folate deficiency anaemia, which can cause tiredness and other symptoms.

Folic acid will help you make healthy red blood cells and improve or prevent the symptoms of anaemia.

In pregnancy

A baby's body and most of their internal organs are formed during the first 12 weeks of pregnancy. Folic acid helps this happen normally.

Low folate levels at this important time can increase the risk of neural tube defects and possibly other problems in your baby.

You need up to 10 times more folate in pregnancy to help your baby develop.

It's recommended that if you're pregnant or trying for a baby, you take a folic acid supplement until you're 12 weeks pregnant.

To reduce the side effects of methotrexate

Methotrexate works by blocking some of the effects of folate.

Sometimes taking methotrexate leads to folate deficiency because it causes your body to get rid of more folate than normal.

Taking folic acid can help prevent folate deficiency.

How long does folic acid take to work?

Folic acid usually starts to work in a few hours.

But if you're taking it for folate deficiency anaemia, it may be a few weeks before you start to feel better.

It's important to keep taking your folic acid for as long as it's recommended.

Are there other sources of folate?

Folate is found naturally in foods, and some foods are fortified with folic acid, which means the vitamin is added to it.

Good sources of folate include:

  • spinach, kale, asparagus, brussels sprouts, cabbage and broccoli
  • peas, lentils and beans, including chickpeas and black eyed beans
  • yeast and beef extracts, including Marmite and Bovril
  • oranges and orange juice
  • wheat bran and other wholegrain foods
  • poultry, pork, shellfish and liver
  • fortified foods with added folic acid, including some brands of breakfast cereals
Do I need to take folic acid in pregnancy if I already eat foods that contain folate?

Yes, you still need to take folic acid.

You need up to 10 times more folate in pregnancy to help your baby grow.

It's unlikely that you would be able to have this much through diet alone.

Why do I need to take folic acid before getting pregnant?

A baby's neural tube starts developing in the first 4 weeks of pregnancy (before your first missed period).

So it's best to start taking folic acid as soon as you start trying to get pregnant.

In the UK and Ireland in the 1980s, before women were advised to take folic acid supplements, about 1 in 200 pregnancies resulted in a baby with a neural tube defect.

Taking folic acid in early pregnancy reduces this risk to 1 in every 400.

What happens if I do not take folic acid before getting pregnant or during early pregnancy?

Do not worry if you have not taken folic acid before conceiving or in the first 12 weeks of pregnancy. It is still likely that your baby will develop normally. Routine ultrasound checks at around 12 and 20 weeks will detect if there are any concerns.

Your midwife will discuss folic acid with you at your first booking appointment and will be able to advise if you need it or not.

Will it affect my contraception?

Folic acid will not stop any type of contraception working, including the combined pill and emergency contraception.

Can I drive or ride a bike?

Yes, you can. Folic acid does not affect you being able to drive or cycle.

Can I drink alcohol while taking folic acid?

It's best to avoid drinking alcohol with folic acid as alcohol may stop folic acid being absorbed. Your folic acid may not work as well.

It's safer not to drink any alcohol if you're pregnant or trying to get pregnant because it can damage your baby's growth.

Is there any food or drink I need to avoid?

You can eat and drink normally while taking folic acid.

Page last reviewed: 5 April 2022
Next review due: 5 April 2025