Folate (vitamin B11): with a wish to conceive and with fatigue

What folate does in your body

Folate is a B vitamin your body needs to divide cells and build DNA. Wherever new cells are formed quickly it is indispensable: in your bone marrow, in your gut wall and in the early development of an unborn child.

In food the natural form is called folate. It is found mainly in green leafy vegetables, pulses, wholegrain products, nuts and liver. Folic acid is the form used in supplements and fortified products.

Your body stores relatively little of it. A deficiency can therefore develop within a few months if intake is structurally too low or if the requirement rises, for example during pregnancy.

A wish to conceive: supplementing comes first, testing rarely follows

Around conception, folate is known for one reason: it lowers the chance of a neural tube defect, in which the spinal cord and brain do not close properly. That development takes place in the first weeks, often before a pregnancy is even noticed.

That is why the national advice in the Netherlands is to take folic acid from the moment you want to conceive up to and including the tenth week of pregnancy. Which dose suits you is something to discuss with your GP, midwife or pharmacy.

And that is exactly the nuance: because the advice is to supplement regardless, a blood test rarely changes it. A normal result is no reason to skip supplementation.

Testing can be useful when there is reason to doubt absorption, for example with a bowel condition, with medication affecting folate metabolism, or if a deficiency has been established before. Discuss that with your doctor.

Fatigue: here testing does add something

With persistent fatigue the picture is different. A folate deficiency can cause anaemia in which the red blood cells are larger than usual, and that produces exactly the complaints people present with: fatigue, breathlessness on exertion, pallor and irritability.

That picture is often found through a full blood count. If the red blood cells are larger than usual, folate and vitamin B12 are the logical next step.

Other complaints mentioned are a sore or smooth tongue, cracks at the corners of the mouth and low mood. None of them prove anything on their own, but together with an abnormal blood count they form a pattern.

Bear in mind at the same time that folate is rarely the only explanation for persistent fatigue. Iron deficiency, a thyroid out of balance and a lack of vitamin D are more common in the Netherlands. That is why folate is usually assessed together with those values rather than as a lone suspect.

Why vitamin B12 always belongs with it

This is the most important point of this article. Folate and vitamin B12 work together in the same processes and produce a very similar blood picture when deficient.

If you take folic acid while you actually have a B12 deficiency, the anaemia can improve while the underlying B12 problem continues. It is that B12 deficiency which can cause nerve damage over time, with tingling, loss of sensation or an unsteady gait.

That is why both values are measured together in practice, and why the B12 status is clarified first when there is doubt, before folic acid is started.

When a low folate is more likely

A deficiency rarely appears out of nowhere. These situations raise the chance:

• eating few vegetables and pulses, or eating one-sidedly after a period of illness
• regular heavy alcohol use, which disturbs absorption and metabolism
• bowel conditions such as coeliac disease or Crohn's disease
• medication affecting folate metabolism, such as methotrexate and some anti-epileptics
• pregnancy and breastfeeding, when the requirement rises
• conditions in which red blood cells are broken down faster

If you recognise yourself here and have complaints, having your folate measured is more sensible than guessing. If none of this applies and you have no complaints, a single folate test usually adds little.

Practical: how to have it measured

Fasting is not required for folate. What does count is what you took shortly beforehand: a supplement on the morning of the draw can influence the result. A multivitamin or a fortified breakfast product counts too, because folic acid is often added to those.

If you want to know where you stand without supplementation, discuss with your doctor whether you can pause it for a few weeks. Never do that on your own initiative during pregnancy or while trying to conceive.

At Bloodworks you have folate measured without a referral, at one of the more than 800 affiliated collection points across the Netherlands. If you want to look more broadly, the Vitamins, minerals and electrolytes package measures nine values in one draw, including folate, vitamin B12, vitamin D and ferritin.