Folate Deficiency, are you at Risk?

Folate is best known as "the pregnancy vitamin", but it plays a far more active role in the body than most people realise — and deficiency is more common than you might expect.

What is folate?

Folate, also called vitamin B9, is one of the eight B vitamins. It is essential for producing healthy red blood cells, building and repairing DNA, and supporting cell division. That makes it particularly important during periods of rapid growth: infancy, childhood, puberty and pregnancy.

A quick distinction that matters: folate is the form found naturally in food, while folic acid is the synthetic form used in supplements and fortified foods. Folic acid is actually absorbed more efficiently, which is why supplements are recommended in pregnancy.

Folate is water-soluble, meaning your body does not store meaningful reserves — excess is lost in urine and sweat. That is why intake needs to be regular rather than occasional.

How much do you need?

Most adults: around 200 mcg a day (UK reference intake)
Trying to conceive and first 12 weeks of pregnancy: 400 mcg of folic acid daily as a supplement, in addition to dietary folate
Higher-risk pregnancies (previous neural tube defect, diabetes, certain medications, higher BMI): a much higher dose may be prescribed — this must be decided by a clinician
Breastfeeding: requirements remain elevated

Signs of deficiency

Early symptoms are easily dismissed: fatigue, irritability, weakness and poor concentration. As deficiency progresses it can cause megaloblastic anaemia, where the body produces abnormally large, underdeveloped red blood cells that cannot carry oxygen efficiently. Signs include pronounced tiredness, pale skin, breathlessness, headaches, palpitations, mouth ulcers and a sore, red tongue.

What causes it?

Diet. Low intake of vegetables, fruit and pulses is the most common cause. Roughly 30 g of leafy greens provides around 58 mcg of folate.

Alcohol. Interferes with folate absorption and increases its excretion.

Malabsorption. Coeliac disease, Crohn's disease and other gut conditions reduce how much folate you absorb.

Medications. Methotrexate, some anti-epileptics, sulfasalazine and long-term metformin can all affect folate status.

Genetics. Your body must convert folate into its active form, methylfolate. Common variants in the MTHFR gene reduce the efficiency of that conversion, which in some people leads to lower active folate and raised homocysteine levels. Where relevant, a supplement already in the methylfolate form may be discussed with a clinician.

Food sources

Leafy greens — spinach, kale, spring greens, rocket
Broccoli, Brussels sprouts and asparagus
Chickpeas, lentils, kidney beans and black-eyed peas
Citrus fruit and juices
Beetroot, avocado and peas
Liver (very rich in folate, but avoid in pregnancy due to vitamin A)
Fortified breakfast cereals and, in the UK, fortified flour

Folate is heat-sensitive — steaming or eating vegetables raw preserves more of it than prolonged boiling.

An important caution

High-dose folic acid can mask an underlying vitamin B12 deficiency, correcting the anaemia while allowing neurological damage to progress undetected. For this reason, B12 should be checked alongside folate before starting high-dose supplementation — particularly in older adults and people following a vegan diet.

Checking your folate levels

Rightangled's home blood tests can assess folate, vitamin B12 and full blood count together, processed by accredited UK laboratories. Results are reviewed by our clinical team, which includes GPhC-registered independent prescribers, with medical oversight from our doctor, Dr Abdullah, so you get an interpretation rather than just a number.

Verify us with the General Pharmaceutical Council (registration 9011933), see our LegitScript certification, and read reviews on Trustpilot.

This article is for general information and does not replace personalised medical advice. If you are pregnant or trying to conceive, speak to your GP or midwife about folic acid.