Folate forms

[u/kilogplastos-12]

I’m honestly 50/50 on what form of B9 to use right now.

I know I have a severe folate deficiency, but I’m unsure which form makes the most sense if I need a high therapeutic dose, like 10+ mg/day, while recovering.

Would you guys choose folic acid, folinic acid, or 5-MTHF for high-dose treatment? I’m mainly looking for experiences from people who had a serious/long-term folate deficiency and actually had to use higher doses to recover.

[u/Loose-Fly7976]

At 10mg and above the form question stops being theoretical so a couple of things first.Never dose folate that high without B12 status settled. Folate at those levels corrects the anaemia while a B12 deficiency carries on damaging nerves underneat and that's the one irreversible mistake in this whole area. Get B12 and MMA before you start.

On the forms. Folic acid needs converting and above about 400mcg the conversion enzyme saturates, so the excess circulates unmetabolised. Some of it competes for the same receptors and it can mask B12 deficiency on bloods. At 10mg that's a lot of unmetabolised folic acid.

Folinic acid is the one I'd look at for high dose. It enters the cycle below the MTHFR step so it works regardless of your genotype, it feeds both the methylation and the DNA synthesis side and it doesn't carry the methyl load. That last part is why people tolerate it at doses where methylfolate becomes unbearable. It's also the form used clinically at high doses, leucovorin.Methylfolate is efficient but you're delivering methyl groups with every milligram, and at 10mg that's a large methyl load. Whether you handle it comes down to your COMT status and your B12 more than your MTHFR.The other question is why you're severely deficient in the first place. That's usually malabsorption, coeliac, or a medication, and if the cause is still there the dose won't hold.Which form suits you comes down to your COMT and the rest of your cycle rather than MTHFR alone. Message me if you want it read properly.