Folic Acid blog post

In Ireland, there are ads on the radio, promoting a brand of folic acid. It sounds like a public health announcement. The pleasant sounding woman tells us that whether we’re planning a pregnancy or already pregnant, we should take 0.4mg (400 micrograms) of folic acid every day to protect our babies from spinia bifida and other Neural Tube Defects. Maybe the general population is unaware, but I think it’s safe to say that any woman with fertility issues knows about folic acid. We’re all taking it or have been advised to take it, right?

What about when you’re beginning a cycle of IVF? Or have suffered recurrent miscarriage? What then?

The standard prescription for anyone having IVF or almost any kind of fertility treatment is 5mg of folic acid daily. That’s 12.5 times the recommended daily amount. Sounds like a lot, doesn’t it? The justification for recommending such a high dose is based on a woman’s perceived risk of having a baby with a neural tube defect (NTD). There are a few factors that can influence this recommendation including 1) Low dietary intake of folate 2) Elevated folate requirement & 3) Uncertain disease etiology.

What the heck does all that mean?

Before I get into the nitty gritty, I want to draw your attention to something. Did you notice in the description above that the name has changed from folic acid to folate? That’s because folic acid is synthetic and folate is the form you find in food. The plot thickens…

A bit more on each scenario that would demand a high dose like 5mg.
  1. Low dietary intake of folate basically refers to how much you’re getting in your diet. If you don’t eat much green veg or perhaps stew the life out of everything you do eat, then you won’t have much folate in your diet. Many foods are fortified with folic acid (like cereals and bread) so these would be considered a source too, although the source is synthetic.
  2. Elevated folate requirement means you have a higher need. Why would that be? Well, maybe you have a family history of neural tube defects or other congenital abnormalities. Perhaps you’re taking medication that interferes with folate metabolism. Perhaps you have issues with gut function which means you don’t absorb folate well from the food you eat.
  3. The 3rd scenario that would justify a high dose of folic acid is “uncertain disease etiology.” What now? Well, if you are diabetic, have issues metabolising glucose or have blood sugar issues of any kind these are considered to be risk factors for a NTD. Being obese is also considered to be a risk factor. It is uncertain whether or not folate metabolism plays a role, but just in case, you will be prescribed a high dose of folic acid.
Stay with me…here comes the science bit

I have a few concerns about how folic acid is prescribed. First of all, it seems that every woman having fertility treatment is prescribed 5mg of folic acid, whether she fits the above criteria or not. Secondly, there is a growing body of evidence indicating that not everyone can metabolise folic acid. One of the best understood reasons for this is a genetic defect (affecting 20-40% of the population) with the MTHFR gene, meaning the MTHFR (Methylenetetrahydrofolate reductase) enzyme won’t work properly & can’t metabolize either folic acid or folate leading to a potential host of problems.

Folate isn’t just responsible for preventing NTD’s, it also plays a crucial role in DNA production and repair, methylation, neurotransmitter production, and red and white blood cell production. All pretty important for your own health but also that of a developing baby. 

I have a hunch that if we were to study those of us affected by fertility issues, the percentage with the MTHFR defect would be much higher than in the general population. Therefore prescribing high doses of folic acid is not only unhelpful, it could be dangerous.

It’s possible that a healthy woman (or man) could metabolise folic acid or folate (from food) but not likely. You would need the MTHFR enzyme & MTHFD1 enzyme to be functioning in order to convert folic acid to 5-MTHF or methylfolate, as well as sufficient levels of B2, B3, B6, B12, Vitamin C, Zinc and normal levels of stomach acid. Even if you could successfully convert folic acid to the active methylfolate, you may not have enough acidity in your gut to properly absorb it.

So what happens to all the folic acid you’re taking, if you can’t metabolise it?

It becomes unmetabolised folic acid and can decrease natural killer cell activity, mask a B12 deficiency as well as inhibit the MTHFR enzyme. Not something I’d want floating around in my body…

What’s the answer then?

The best approach is to get tested for the MTHFR defect. If you know for sure whether or not you are affected, it’s much easier to decide if folic acid is appropriate. If you simply cannot afford another test, use the checklist below to see if you fit the criteria for ‘Poor Methylation’ which may indicate that you have the defect or have issues with absorption. Failing those options, assume that you cannot utilise folic acid and take the methylfolate form. This form is in a state that does not need to be converted to anything. It is ready to go and understood to be 3 times more potent than folic acid. Most women could assume a dose of 150 micrograms to be sufficient, but if you have a history of miscarriage or numerous unsuccessful IVF cycles it may be worth increasing the dose to 1.5mg daily (which approximately matches the standard 5mg prescription for folic acid).

If you can, I’d strongly recommend having a consultation with a nutritional therapist or naturopath who understands this issue and can support you in making the best choices.

Checklist for Poor Methylators

Side note: Because B12 is part of the methylation cycle, I’d also suggest taking the methylated form of B12, called methylcobalamin. This is another nutrient that is commonly deficient and difficult to absorb, but it can be taken in liquid form under the tongue.

Is your head melted? Have questions? Please, ask them in the comments section below and I will do my very best to answer them. If you’ve found this blog post useful, please spread some love and share it with your online family.

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This blog post is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment and before undertaking a new health care regimen.