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Folinic Acid

There's quite a bit of confusion in the health world about the difference between a few important, uh, "F words." Of course, I mean folate, folic acid, methylfolate and folinic acid. Even if you're not completely sure of what these terms mean, you've likely heard them before. Before we get into what folinic acid is, let's cover the other definitions first (because they're all connected).

Folate - Folate is the naturally occurring dietary form of vitamin B9. Common sources include dark leafy greens, asparagus, broccoli, oranges, avocados, Brussels sprouts, seeds, nuts, and beans. You really can't go wrong with natural folate, as vitamin B9 is critical for methylation. A diet that is rich in natural folate will always benefit someone with an MTHFR variant!

Folic Acid - Folic acid is a bit of a dirty word around here. You will often hear that folic acid and folate are interchangeable, but that's not quite true. Folic acid is a man-made, synthetic form of Vitamin B9 that does not share the same molecular structure. Due to this difference in structure, those with an MTHFR variant have a difficult time processing it correctly. This is because the different structure requires an extra step of conversion with the MTHFR enzyme that we tend to be short on. Not only will folic acid do little to benefit a MTHFR's methylation process, but it can actually block dietary folate and other more bioavailable forms of supplemental folate from doing their jobs. It's important to remove folic acid from your supplements and your diet (in the form of enriched foods).

Methylfolate - Methylfolate is a supplemental form of Vitamin B9 that shares the same molecular structure as dietary folate. For this reason, it does not require that extra step of conversion that folic acid requires. In other words, it is bioavailable and easily absorbed and processed. It is a great alternative to folic acid for someone with an MTHFR variant. The only problem is that some people with an MTHFR variant experience unpleasant side-effects from this form of supplemental folate. That's where folinic acid comes into the picture.

Folinic Acid - Folinic acid, not to be confused with folic acid, is another bioavailable form of supplemental folate that could benefit someone with an MTHFR variant. While getting adequate Vitamin B9 through diet and/or supplementation is critical for methylation, some people with an MTHFR variant still do not tolerate methylated vitamins well. This is the main reason that someone may turn to folinic acid rather than methylfolate. Folinic acid is yet another bioavailable form of folate that does not tend to cause some of the icky symptoms that methylfolate is sometimes associated with.

Folinic acid could be for you if methylfolate causes any of the following symptoms:

  • Irritability

  • Confusion

  • Difficulty sleeping

  • Headaches

  • Nausea

  • Depression

  • Anxiety

So which is better, methylfolate or folinic acid? I would say it depends on your body and unique needs. Both forms of supplemental folate are bioavailable, easily absorbed, and offer excellent benefits. While methylfolate tends to be the standard, you really can't go wrong with folinic acid either!


To take a deeper, guided dive into how to thrive with an MTHFR variant, check out Hey MTHFR Academy. This 16-week online course will give you the tools you need to harness the power of epigenetics and befriend your MTHFR gene.



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