What are the benefits of folic acid for women?

What are the benefits of folic acid for women?

Folic acid is the man-made form of folate, also called vitamin B9. Its proven benefit is for pregnancy.

It cuts the chance of a neural tube defect, a problem with a baby’s brain or spine, such as spina bifida.

A Cochrane review pooled five trials and 6,708 births. Women given folic acid, alone or with other vitamins, had about a third as many babies with these defects. The reviewers rated that evidence high quality.

Folate also helps your body form healthy red blood cells. Too little can lead to folate deficiency anaemia, which doctors treat with folic acid tablets.

So the first question is simple: could you get pregnant? If yes, check your tablet says 400 micrograms.

Do all women need folic acid?

No. The NHS says women who cannot get pregnant should be able to get all the folate they need from a varied and balanced diet.

Adults need 200 micrograms of folate a day. Your body keeps no long-term store, so eat folate foods often.

Good sources are broccoli, brussels sprouts, peas, chickpeas and kidney beans. Leafy greens count too: cabbage, kale, spring greens and spinach. So do breakfast cereals with added folic acid.

Liver is rich in folate, but the NHS says to avoid it if you’re pregnant.

From 13 December 2026, non-wholemeal wheat flour in the UK, such as white flour, must have folic acid added. Wholemeal flour is not included. The government says the 400 microgram tablet advice will continue.

Had a blood test? See normal folate levels or what a low folate result means.

How much folic acid should a woman take?

If you could get pregnant, take 400 micrograms every day. The NHS says it’s hard to get enough from food alone.

Some women need a higher dose of 5 mg a day, prescribed by a GP. This is if you’re planning a pregnancy or less than 12 weeks pregnant, and:

• you or the baby’s father has a neural tube defect, or a relative with one
• a past pregnancy was affected by a neural tube defect
• you have diabetes
• you have a blood condition such as sickle cell anaemia or thalassaemia
• you take medicine for epilepsy or HIV

The NHS says the higher dose is unlikely to cause harm, as it’s short term. Speak to your doctor first.

Above 1 mg, folic acid can mask the signs of low B12, which can eventually damage the nervous system. More in B12 deficiency symptoms.

When should women start taking folic acid?

Before you get pregnant. A baby’s brain and spine form within the first 12 weeks, usually before the mother knows she’s pregnant.

That’s the catch from the top of the page: folic acid does its job before most women know they’re pregnant. So the NHS says start before you stop contraception.

Around half of UK pregnancies are unplanned. The NHS advice covers any woman who could get pregnant, not only those trying.

Planning ahead? The fertility blood test guide and omega-3 in pregnancy cover what else to think about.

Folic acid side effects and who should check first

Side effects of the tablets can include bloating, wind, feeling sick and loss of appetite. Not everyone gets them.

Tablets may not suit you if you’ve had an allergic reaction to folic acid, or you have a heart stent, cancer or low B12 anaemia. The same goes for pernicious anaemia, where your immune system attacks your body’s healthy cells. Tell your doctor first.

Some medicines may not mix well with it. These include some epilepsy medicines, some antibiotics, sulfasalazine (a medicine for some bowel and joint conditions), lithium (a mood medicine) and aspirin. Never stop or change a prescribed medicine without your prescriber.

Breastfeeding? Folic acid can usually be taken, but check with a pharmacist or doctor first. To compare labels, see what to look for in a multivitamin for women.

When to speak to a GP

Book an appointment if:

• You’re planning a pregnancy and any of the 5 mg reasons apply: a neural tube defect in you, the baby’s father or a relative, a past affected pregnancy, diabetes, sickle cell anaemia, thalassaemia, or medicine for epilepsy or HIV.
• You take an epilepsy medicine such as sodium valproate or carbamazepine and could get pregnant. The NHS says these can raise the chance of spina bifida.
• You have signs of low folate or B12: feeling weak or tired, fast breathing or shortness of breath, headaches, a pounding or fluttering heartbeat (palpitations), indigestion, loss of appetite, diarrhoea, a sore or red tongue, sometimes with mouth ulcers, problems with your vision, or problems with memory, understanding and judgement. Low B12 can also cause pins and needles. The NHS says to get it treated as soon as possible.
• You have side effects that bother you or do not go away. A pharmacist can help with this too.

Call 111 if you’ve taken more than your prescribed dose, or more multivitamins than the label says. Call 111 too if you think you’re having a serious side effect. Signs include a swollen face, throat or tongue, an itchy raised rash or difficulty breathing.