Why Must Everyone Take Folic Acid for the Few?

From December 2026, folic acid fortification in the UK will become mandatory for most non-wholemeal common wheat flour. It means folic acid will be added by law to flour used in an enormous range of everyday foods, from the ordinary white loaf to cakes, biscuits, pastries and plenty of other products most of us buy without giving the flour in them a second thought.

I hate that we’re doing this. Not because I think folic acid is a poison, because it isn’t, and not because I doubt that it can prevent serious birth defects when women get enough of it before and during early pregnancy. That benefit is well established. I object because we’ve identified a genuine health need among a particular section of the population and decided that one answer is to alter a staple food eaten by almost everybody.

There is another part of this that matters to me too. Folic acid isn’t something for which scientists have never had to consider possible adverse effects. Britain’s own scientific advisers have investigated sustained high intakes in relation to vitamin B12 deficiency and neurological damage, cognitive decline, cancer risk and unmetabolised folic acid in the blood. That does not mean fortified flour has been shown to cause those diseases. It hasn’t. But when millions of people who receive none of the intended pregnancy benefit are being made to consume additional folic acid too, I don’t think those questions should simply be waved away.

Why folic acid matters in pregnancy

Folate, or vitamin B9, is something all of us need. It occurs naturally in foods including leafy green vegetables, broccoli, peas and beans. Folic acid is the manufactured form used in supplements and food fortification.

The NHS advises women who are pregnant, trying for a baby or could become pregnant to take folic acid every day, ideally beginning before conception and continuing through the first 12 weeks of pregnancy. Some women at greater risk are advised to take a higher dose.

There is a very good reason for starting early. The neural tube develops in the first few weeks of pregnancy and eventually forms the baby’s brain and spinal cord. By the time some women discover they are pregnant, part of that crucial period has already passed.

That gives supporters of mandatory fortification a strong argument. Pregnancies aren’t always planned, supplements aren’t always taken and no information campaign is ever going to reach every woman before conception. Put folic acid into a staple food and you don’t need to reach her first. She may already be consuming it.

I understand that argument perfectly well. Preventing neural tube defects is an extremely worthwhile aim, and I don’t think opposition to the method requires pretending otherwise. But accepting the benefit doesn’t mean I have to accept the way we’ve chosen to deliver it.

We know who needs it, so why are we giving it to almost everyone?

This is the part I cannot get past. Flour has been chosen precisely because so many people eat it. That makes it an incredibly effective way of reaching women who may become pregnant, including those who weren’t planning to.

It also means everybody else comes along for the ride. Men will consume the additional folic acid. Children will consume it. Pensioners will consume it. Women decades beyond childbearing age will consume it. People who cannot have children will consume it. Their food is being altered not because they have been identified as needing additional folic acid themselves, but because changing everybody’s flour makes it easier to reach somebody else.

I think that’s wrong.

If women aren’t getting enough folic acid before pregnancy, I would rather see us throw everything at solving that problem directly. Make supplements incredibly easy to obtain. Provide them where appropriate through pharmacies and health services. Do a far better job of explaining why folic acid matters before pregnancy rather than expecting women to discover it once they’re already pregnant. Find the groups least likely to take it and work out why. If access or cost is getting in the way, remove those barriers.

Would that reach every woman before every unplanned pregnancy? No. That’s the difficult part of this debate, and pretending otherwise would be dishonest. But I don’t accept that because targeted measures cannot achieve perfection, changing a staple ingredient for almost everybody automatically becomes the right answer. There should be an exceptionally high bar before difficulty reaching one group becomes justification for routinely exposing everybody else.

It won’t just be a little bit in a loaf of bread

From 13 December 2026, most non-wholemeal common wheat flour milled in or imported into the UK will have to contain 0.25mg of folic acid per 100g. Wholemeal common wheat flour is outside this particular requirement, as are flours made from other grains, and there are exemptions including qualifying small mills. The Government sets out the details in its guidance on bread and flour composition.

Flour, of course, doesn’t stay in the flour bag. It becomes bread, cakes, biscuits and pastries, and it is also used in a much wider range of manufactured foods. That’s the whole attraction of using flour as the delivery system: its reach is enormous.

There is something else worth remembering. Mandatory flour fortification isn’t the only possible source of added folic acid in someone’s diet. Folic acid is already used voluntarily in certain fortified foods and is present in supplements and multivitamins.

Someone could therefore eat a voluntarily fortified product at breakfast, consume products made from mandatorily fortified flour during the day and take a supplement containing folic acid as well. That doesn’t mean the person is consuming a dangerous amount, but it does mean their total intake cannot necessarily be judged by looking at the tiny amount in a single slice of bread.

The Government’s scientific advisers haven’t ignored this. Voluntary fortification and supplement use have formed part of the discussion around mandatory fortification because total exposure matters.

There are health questions, whether people like it or not

This is another major reason I dislike the idea of almost everybody consuming additional folic acid for the benefit of a much smaller group. Questions about adverse effects are not something dreamt up by conspiracy theorists on the internet. The Scientific Advisory Committee on Nutrition has considered potential risks associated with sustained high intakes of folic acid, including vitamin B12 deficiency and neurological damage, cognitive decline, cancer risk and the long-term significance of unmetabolised folic acid circulating in the blood.

That needs to be understood properly. SACN investigating those issues is not evidence that folic acid fortification causes cancer, dementia or neurological disease. It isn’t. In several areas the evidence is reassuring, and in others there remains uncertainty. I don’t want to turn legitimate scientific questions into a health scare because there is no need to.

There is, however, a recognised concern involving vitamin B12 deficiency. High folic acid intake can correct the anaemia associated with B12 deficiency without treating the deficiency itself. That can potentially delay diagnosis, while untreated B12 deficiency can cause neurological damage. This is one reason why the amount of folic acid people consume matters rather than there simply being an assumption that more must always be better.

Cancer risk has also been investigated. SACN has reviewed evidence around folic acid and cancer risk, with different types of research not always pointing in the same direction. Its overall assessment has not established that folic acid fortification causes cancer, and I wouldn’t claim that it does. What matters to me is that potential adverse effects have been serious enough to investigate in the first place when we’re now deliberately increasing exposure across almost the entire population.

Cognitive decline has been examined too, particularly among older people and in relation to vitamin B12 status. Again, the evidence does not establish that folic acid causes dementia. There is no justification for telling people that eating fortified bread is going to give them dementia, and that isn’t the argument I’m making.

Then there is unmetabolised folic acid, or UMFA. Small amounts can be detected in the bloodstream, and scientists have looked at whether this might have long-term health implications. The available evidence has not established that UMFA causes disease. That is reassuring, but it is another area that has required scientific consideration as exposure to folic acid has increased.

So I’m not going to tell people that eating fortified bread will give them cancer, dementia or some other disease. There isn’t evidence to justify saying that. But here’s the part I think matters enormously: if millions of people are being expected to consume additional folic acid because it is the easiest way of reaching a much smaller group, then even potential health concerns among those millions deserve serious consideration.

The people carrying any theoretical downside are not necessarily the people receiving the intended benefit. That changes the calculation for me. If a woman who may become pregnant decides to take folic acid, she is taking something with a clear intended benefit to a possible pregnancy. If an elderly man consumes additional folic acid because it has been put into his flour to protect pregnancies elsewhere in the population, he receives none of that intended benefit.

The Government may conclude that the additional exposure presents very little risk and that preventing neural tube defects outweighs it. Its scientific advisers support mandatory fortification. But that is still a population-level calculation being made on behalf of millions of individuals, and when the intervention is built into a staple ingredient, I think uncertainty matters more, not less.

“It’s only a vitamin” isn’t good enough

I can already imagine one response to all of this: it’s folic acid, not some dangerous chemical. That’s true, but it misses the point.

Folic acid has biological effects. That’s precisely why we’re adding it to flour in the first place. If it had no meaningful effect on the human body, it couldn’t help prevent neural tube defects.

The fact that something is a vitamin doesn’t mean quantity suddenly becomes irrelevant. There are recommended intakes, upper guidance levels and specific advice around supplementation for a reason. The sensible discussion isn’t between people claiming folic acid is poisonous and people claiming no amount could ever matter. Neither position is useful.

What matters is dose, total exposure, who benefits, who doesn’t, what risks are established, what questions remain unresolved and whether exposing a much larger population is proportionate to the benefit we’re trying to achieve.

Then there is the question of choice

Health isn’t my only objection. I don’t like the principle of government deciding that an everyday staple should become the delivery mechanism for a public health intervention aimed principally at another group of people.

Consumer choice was raised during the Government’s own consultations. Some respondents objected specifically because they believed mandatory fortification removed their ability to decide whether they consumed additional folic acid. Some used descriptions such as “mass medication” and “nanny state”. I wouldn’t call it medication myself because folic acid is a vitamin, and I think that language makes it too easy to dismiss the underlying point.

The underlying point is strong enough without it.

Technically, people will still have choices. Wholemeal common wheat flour is outside this particular folic acid requirement, other types of flour are available and flour produced by qualifying small mills is exempt. If somebody is determined to avoid mandatorily fortified flour, it can be done.

But why should the person who doesn’t want it be the one who has to change?

If I’ve eaten an ordinary white loaf for decades and don’t want additional folic acid added to it, why should I now have to seek out something different? Why does the altered product become the default while opting out requires me to change my habits?

I’d have far less objection to clearly labelled fortified products sitting alongside ordinary ones. Explain the pregnancy benefits properly. Encourage women who may become pregnant to use them. Make them readily available and affordable. Combine them with much better education and easy access to supplements. Give people a reason to choose them.

Instead, we’ve chosen to change the default.

The women who need folic acid will still be told to take it

There is another detail that makes the whole thing harder for me to accept. Mandatory flour fortification doesn’t replace the existing advice for women who may become pregnant to take folic acid supplements.

They will still be advised to take folic acid before conception and during early pregnancy. Fortification is intended to support that advice, not replace it. So the targeted intervention remains, while a population-wide intervention is being placed underneath it as a safety net for women the targeted advice doesn’t reach.

I understand exactly why policymakers find that attractive. If a pregnancy is unplanned, the safety net may be there when the supplement isn’t. But let’s be clear about what follows from that decision. We’re not adding folic acid to everyone’s flour because everybody has suddenly been identified as needing more folic acid for their own health. We’re doing it largely because some of the people who particularly need additional folic acid aren’t being reached reliably enough before pregnancy.

That’s the principle I object to.

Before changing everybody’s food, I want to know that we’ve done everything reasonably possible to fix the targeted approach. I want women to know about folic acid before pregnancy. I want supplements easily accessible. I want us to understand why some women aren’t taking them and address those reasons properly.

I don’t want “we can’t reach everybody” to become an easy justification for “so everybody gets it”.

I don’t think this should become normal

This is bigger than whether one slice of bread contains a tiny amount of folic acid. Food is fundamental. Everybody has to eat, and staple foods are consumed day after day for decades. Once government decides that changing those foods is an acceptable way of delivering an intervention to a particular section of society, I think the threshold for doing it should be exceptionally high.

Britain already requires certain nutrients to be added to non-wholemeal flour, so folic acid isn’t the beginning of food fortification in this country. Nor are we the first country to adopt mandatory folic acid fortification. None of that means we should stop questioning each new intervention on its own merits.

For me, folic acid fortification in the UK doesn’t pass that test comfortably enough. The intended benefit is concentrated around pregnancy while the intervention reaches almost everybody. There are genuine scientific questions around high folic acid exposure, even though the evidence does not show that the fortification level we’re introducing causes cancer, dementia or other diseases. There is also the basic question of whether people should have to change what they buy if they don’t want an additional nutrient put into their food.

I don’t like any of that.

The benefits are real. I still oppose it.

This would be an easier article to write if I pretended there were no good arguments on the other side. There are. Folic acid can prevent devastating neural tube defects. Pregnancies aren’t always planned. The crucial period begins extremely early. Supplements won’t reach everybody. Putting folic acid into flour can reach women who would otherwise miss that protection.

I understand all of it. I still think we’re doing this the wrong way.

If women who may become pregnant need additional folic acid, move heaven and earth to get it to them. Improve education. Make supplements readily available. Target the groups we’re failing to reach. Spend money on doing it properly. Make sure women understand that folic acid matters before conception, not simply after a positive pregnancy test.

And if government still believes changing almost everybody’s flour is necessary, then the burden should be on government to keep demonstrating that the benefit justifies increasing the intake of millions of people who receive no intended pregnancy benefit themselves.

That matters particularly because health questions around folic acid have existed and have been investigated. We shouldn’t exaggerate those questions into claims of proven disease, but nor should we pretend they become irrelevant because the expected risk is small. When millions of people are consuming something to benefit a much smaller group, even a potential downside to those millions belongs in the argument.

Most of all, I want the presumption to remain that what goes into our food is our choice unless there is an overwhelmingly strong reason to take that choice away.

Preventing birth defects is an exceptionally good reason to act. I simply don’t believe we’ve shown that changing everybody else’s food is the only acceptable way to act.

If additional folic acid is principally needed to protect women who may become pregnant and their babies, get it to those women. Don’t put it into almost everybody’s food because reaching them directly is harder.