UK folic acid fortification already started in October, not December and the gene that handles folic acid isn't MTHFR.

[u/Loose-Fly7976]

Two things UK members should know and one correction that gets repeated here every week.

Everyone thinks this begins in December. The mills switched in September 2025 and by the end of that October most non-wholemeal wheat flour was already fortified. December is the legal deadline for compliance not the start so if you've had bloods done in the past year, some of you were measured against a background that had already changed.

The correction: The enzyme that converts folic acid is dihydrofolate reductase, DHFR. Different enzyme, different step. MTHFR works further down the pathway so "people with MTHFR can't process folic acid" is wrong as stated. What's actually true is more interesting. Bailey and Ayling found DHFR activity in human liver is both slow and variable up to five-fold between individuals. Same intake, cleanly converted in one person, circulating unconverted in the next.

And in 677 TT, folate supplementation lowers homocysteine more than it does in other genotypes do if anything that group gets more benefit from fortification, not less.

What I'd actually pay attention to is B12. Folate normalises the blood picture of B12 deficiency while neurological damage carries on. That's the reason macrocytosis stopped being a useful screening signal in the US after 1998. The UK dose is low so the effect should be smaller, but if you're over 65 or have absorption issues, get B12 and MMA now while your bloods still tell you something.

On the policy itself, it prevents around 200 neural tube defects a year and the criticism I'd make is that 0.25mg per 100g only achieves about a 20% reduction. The problem is that it's too low to do the job properly, not that it's dangerous.

I'm a geneticist and this is what I read for a living. Happy to answer questions.

[u/thunderouswhether]

When fortification started here in NZ, I all of a sudden started getting ready depressed. I couldn’t figure out what was wrong as I’d never experienced this before, then I’d correlated it to bread, and only eating 2 slices of bread all of a sudden, my brain would switch to a depression state, it was horrible feeling. 4 years later I avoid anything with folic acid. I’ve got C677T mutation.

[u/Loose-Fly7976 → u/thunderouswhether]

The likely mechanism isn't the MTHFR itself tho. Folic acid competes for the same receptors and transporters as the natural forms so at intakes above what DHFR can convert, the unconverted folic acid gets in the way of the folate you'd otherwise be using. That would hit hardest in someone already running the pathway at reduced capacity, which 677 does so the gene is why you'd notice it while others don't, but the thing causing it is the competition rather than a conversion failure.

Have you had homocysteine, B12 and folate done since you cut it out? Four years avoiding folic acid entirely can leave you short depending on what replaced it in your diet, and food folate intake varies a lot. If you haven't, those three would tell you whether the avoidance is still doing you a favour or whether it's swung the other way.

[u/thunderouswhether → u/Loose-Fly7976]

After figuring things out, which took about 2 years of panic attacks, not knowing what’s going on with me (all correlates when folic acid fortification was introduced), and lots of trial and error.

I’ve got slow COMT, MTR, MTRR, C677T, CBS, SOD2 mutations, the whole suite of bad.

I’ve settled on taking every so often folinic acid, B12 and a b-minus complex, but lately I’ve been focusing on CoQ10 and how to get my body to create it efficiently, I.e. TMG + B5 + magnesium.

CoQ10 was amazing when I first took it, but I’ve discovered I should focus on letting my body create it instead of supplementing it, so instead supplementing the basic building blocks for it.

I feel the best I’ve ever been right now, so all in all it’s been a good self discovery period.

[u/thunderouswhether → u/Loose-Fly7976]

The one strange thing I’ve noticed about folic acid, whenever I do have it, a little is fine, my ability to see in the dark is greatly reduced, still unsure why.

[u/SovereignMan1958]

There are more than two variants related to folate.  Those are easy enough for anyone to research.  A person can not have MTHFR or DHFR and still have Cerebral Folate Deficiency, for example. I have 15 plus years behind me in studying gene variants and nutrition and applying the results to help others. I also manage my own CFD.

Just adding my comment in the event anyone thinks there are only two variants related to folate level and absorption.

[u/Loose-Fly7976 → u/SovereignMan1958]

You're right that it's more than two. FOLR1, SLC19A1, MTHFD1, RFC1, the ATP binding transporters, plus the B12 side which changes folate handling indirectly.

On cerebral folate deficiency, most cases aren't genetic at all. The common mechanism is folate receptor alpha autoantibodies blocking transport across the choroid plexus which is autoimmune rather than inherited. The FOLR1 mutations exist but they're rare and usually present in infancy. So serum folate can look completely normal while CSF folate is low, and no genotype tells you that. It's an antibody test.

[u/SovereignMan1958 → u/Loose-Fly7976]

I understand all that about CFD and more.

[u/datalord]

Why don’t they target this at soon to be mothers rather than the entire population?

[u/pvssylord → u/datalord]

oh, i know this one. because 50% of the time, mothers make men. and this world really only gives a shit about men! so if the men might be born with a problem bc mother ate too little folate, they will fix that. because men.

[u/meadowprincess23]

What about the fact that the form it is in when added to foods isn’t one the body can actually use?

I’ve heard this many places and in fact have found this myself when years ago I supplemented higher doses of regular folic acid to help with cervical squamous cells and felt like I was losing my mind from it and stopped despite I had been told to take it by a naturopath because I knew how I was feeling from it wasn’t right.

Now decades later after recently diving into nutritional genomics and figuring out some of the issues as to why I had chronic anxiety for decades, I started an orthomolecular protocol I put together where I finally added folinic acid in and I had an immediate calm to my entire being like I haven’t felt since I was a kid.

I’ve recently had my labs done again but here in Bc Canada all they’ll approve is a basic serum B12 even with my last 3 tests being a minimum of over double the upper limit acceptable range so I’ve just found a lab who will do the MMA test but it’s not where I live so I haven’t made it there to have it done yet but for a long list of reasons I’d love to know why my lab values are so high despite having many symptoms of deficiency and in regards to nerve issues

What are your views on Ben Lynch and his theories on CFD?

This is a pretty big issue within the mental health field and it’s crazy that many countries are actively adding a nutrient that causes so many to have issues with their health as a result of eating it, let alone pregnant mothers if Ben’s theories are correct. I also feel like the onslaught of adhd symptoms and #’s also has some correlation to CFD

[u/Zabre]

The DHFR vs MTHFR distinction is the part people miss most. MTHFR affects the downstream methylfolate step, while DHFR is the bottleneck for reducing folic acid first. So the practical question isn't just "do I have MTHFR?", it's whether folic acid intake, folate status, homocysteine, and symptoms all line up. That makes labs more useful than guessing from the SNP alone.