Reality behind the claim folic acid could “save 200 babies”

Modelling and false assumptions have led to an inflated number

Dr Clare Craig

Key points

The government said fortification would “help avoid around 200” neural tube defects a year and that “hundreds more babies will be born healthy”.

Of the “200”, only 31 are live births, about 28 would be children living with disability and 3 are fatal cases that do not survive. Most of the claimed effect of the policy is to reduce terminations.

The “200” comes from a modelled 20 percent reduction applied to an assumed baseline of 1,000 pregnancies. But were are only 621 affected pregnancies in England in 2022 and the final assessment used 800.

The economic case values a life-year at £70,000, more than double the £20,000 to £30,000 the NHS uses for medicines.

Of the £683 million headline benefit, £571 million is a notional value placed on quality of life and only about £20 million is money the health service would actually save over ten years. The £85 million cost falls on industry and consumers.

No assessment was made of the ethics of medicating 69 million people, and no risk-benefit assessment was done. Potential harms to others were named but not given a value.

From 13 December 2026, the Bread and Flour (Amendment) Regulations 2024 require folic acid to be added to all non-wholemeal wheat flour milled in the United Kingdom. The justification for mandatory fortification rests on a modelled claim that around 200 babies a year will be saved. When it was announced in September 2021, the Department said fortification would “help avoid around 200 neural tube defects each year”, roughly 20 percent of the annual UK total.

The wording was carefully chosen:

• The verb is “help avoid” rather than “prevent”.

• The word “around” is there because the number is modelled.

• And the unit is neural tube defects, not live births with a neural tube defect, so it counts every affected terminated pregnancy and other pregnancy losses, across more than one condition.

In the same announcement the then Health and Social Care Secretary, Sajid Javid, was quoted as saying:

“We are committed to giving more children a healthy start in life. With the safe and taste-free folic acid baked into the national diet, hundreds more babies will be born healthy each year.”

The government’s own figures do not come close to that. The 200 figure relates to pregnancies not babies currently born living with a future of disability ahead of them.

Before digging into the numbers it is worth making one more point. The only assessment the government carried out for this measure was financial. There is no published consideration of the ethics of medicating a whole population without individual consent and there was no risk-benefit assessment of modelled gain against the potential harms to others.

How many pregnancies are affected?

The government’s 200 babies figure came from an estimate of 1,000 affected pregnancies a year and a claim that they could reduce that by 20%. The 1,000 figure does not stack up.

According to the most recent NHS data, in 2022 there were 621 pregnancies affected by a neural tube defect in England. Extrapolating to the UK gives approximately 731. Of the 621, some 57 are recorded alongside a genomic condition, a chromosomal or single-gene disorder that folic acid cannot affect. At most 564 could even in principle be folate-related in England or 663 in UK. That is a long way from 1,000.

Neural tube defect pregnancy outcomes for 2022, from the NCARDRS Congenital Condition Statistics Report for England; UK figures extrapolated by relative birth numbers.

With only 170 live affected babies born each year in UK currently, and, if a 20% reduction were possible only 146 fewer affected pregnancies, it is quite the stretch to say “hundreds more babies will be born healthy each year”.

The government’s own final assessment records about 165 live NTD births a year and estimates that fortification would prevent 31 of them. So even on the government’s figures the operative effect is 31 fewer live births, of which about 28 would be children living with disability and 3 are averted fatal anencephaly cases.

What conditions are included?

A neural tube defect is not one condition. On the model’s own split, the pregnancies it prevents are roughly two fifths anencephaly, one in eight encephalocele, and about half spina bifida.

Anencephaly is not survivable and encephalocele rarely so. Only the spina bifida group contains substantial numbers of surviving children. Even accepting the government’s assumptions, the principal measurable effect is around a hundred fewer terminations following prenatal diagnosis each year, roughly 0.04 percent of terminations nationally.

Where the 200 comes from

Rather than count recorded cases, the first impact assessment began from an assumed 1,000 affected pregnancies a year, well above the actual record of around 731 in 2022. How did they get to 1,000? First, they took a birth projection about 14 percent above reality and then applied an affected rate about 18 percent above the actual rate, leaving the starting figure roughly a third too high before any further modelling.

The final 2024 assessment lowered the baseline to about 800. They got to 800 by scaling a EUROCAT prevalence rate up to the population of the UK rather than using NCARDRS, the definitive English registry, which recorded 621.

The higher estimate was adopted at both stages. Even taking the final assessment’s own baseline of about 800 affected pregnancies, a 15 to 20 percent reduction would prevent roughly 120 to 160 cases, not 200, and certainly not hundreds.

The 20 percent reduction is itself a modelled output, and an unstable one. The government estimated the reduction ranging from 8 to 24 percent at double the dose proposed.

How the benefit was valued

The government then crafted a purely economic case for fortification.

1. The first assessment valued every prevented case as a whole life

The 2019 consultation assessment priced a quality-adjusted life-year at £60,000 and valued each prevented fatal case at just under £3 million. It did not separate terminations from live births so each prevented termination was valued at £3 million. A life has immeasurable value, but health economics does not price it that way; it assigns a finite figure.

Follow that reasoning out. Applied to the roughly 300,000 terminations carried out in the UK each year, valued the draft’s way, the total comes to around £900 billion, more than four times the entire health budget. If that were the government’s real valuation of a prevented termination, reducing terminations would be the overriding priority of the health service. It is not. The draft also never completed its own totals: every headline cost and benefit line was left marked “to be confirmed”.

2. The final assessment changed how terminations were treated

The day the regulations were changed in 2024, the sums were republished. The whole-life valuation was kept and uprated to £70,000 per quality-adjusted life-year, but applied only to live births not terminations. Prevented terminations were moved to the cost of the procedure avoided, about £500 to £1,600 each. Anencephaly, which is fatal within hours, is given the largest value of the three conditions, £2.9 million a case, because a child who dies at once is counted as losing a whole lifetime. Spina bifida, the condition that produces children who live for decades, is valued lower, at £1.7 million, because a life lived with disability retains some of its worth in the calculation.

The table sets out the comparison of the consultation draft before the regulations were changed and the final publication on the day of the amendments.

One detail inside the anencephaly figure is worth noting. The assessment’s own method, 41.9 discounted life-years at £70,000, produces £2.9 million, yet the document prints £3.2 million, which implies a per-year value above the £70,000 it states it is using.

3. The value placed on a life-year is unusually high

The assessment values a quality-adjusted life-year at £70,000 and describes this as standard Green Book practice. This is a reference to the Treasury’s Green Book not the public health Green Book. However, the Treasury Green book does not give a number and its appendix states £60,000. The £70,000 has been used in answer to parliamentary questions and other government assessments but is not recorded in the Green book as claimed. For comparison, when NICE decides whether the NHS should fund a medicine, it values a quality-adjusted life-year at £20,000 to £30,000, reaching £35,000 only for the most severe conditions. A patient who needed a drug to gain a year of healthy life would have that year valued at no more than £35,000, and usually less. Folic acid’s life-years were valued at twice that ceiling.

Supporters of the higher figure argue that fortification is not paid for from the NHS budget, so no other treatment is displaced, and a societal valuation is appropriate rather than the opportunity-cost threshold NICE applies. Even on that argument it should be £60,000 not £70,000.

Repricing the assessment’s own case figures at the NHS rate gives this:

At the NHS’s own rate the £571 million health benefit falls to about £245 million, and the net benefit of the whole policy from £599 million to about £272 million. It remains positive, but is less than half the figure claimed.

4. The disability figure rests on weak evidence

To turn a life with spina bifida into a quantity of lost health, the assessment adjusts each year lived to be worth 0.55 of a year in full health. That single number underpins the largest benefit stream in the document. It comes from one study of 80 children in Arkansas, aged five and over, assessed around 2004. The children did not rate themselves. Their parents rated them, and the study’s authors caution that “the use of caregivers as proxy informants of their child’s health state, may introduce artificial correlation with their own health state”. The study used a control of healthy unrelated children and their scores overlapped significantly with the scores for children with spina bifida. Affected children ranged from 0.09 to a full 1.00, and healthy children from 0.47 to 1.00. Some children with spina bifida were rated in perfect health, and some healthy children scored below the average for children with spina bifida. Instead of using the difference in scores between the affected and unaffected children, the government used the average score for the children with spina bifida. This score was then extrapolated to every year of life not just childhood.

What the benefit is made of

Set out in full, the £683 million benefit and the £85 million cost over ten years break down as follows.

Of the £683 million headline, £571 million is the monetary value placed on quality of life, and only £19 million is money the health service would actually no longer spend. Set as a straight comparison of real costs against real savings, £85 million of cost (paid for by consumers) is set against about £20 million saved (by the NHS). The upfront costs outweigh the savings by more than four to one. The equation tilts the other way because of quality of life saved.

Who wins, who pays, and what was never counted

A cost-benefit analysis of this kind gives life, health, income and costs a monetary value which can be compared. These can be split out:

The assessment’s own benefit and cost items. Health harms were named in the assessment as non-monetised effects but not assigned a value.

How little harm would cancel the benefit

The net benefit is £599 million. At the £70,000 per quality-adjusted life-year the assessment uses, that is about 8,600 life-years of health. Fortification reaches about 69 million people. Spread across them, the entire net benefit corresponds to only about 0.000125 life-years of harm each, roughly one hour of healthy life lost per person over the whole appraisal period. A harm that small would never appear in any monitoring, and it would be enough to cancel the benefit in full.

Put in terms of a single condition, the margin is just as thin. To erase 8,600 life-years over the ten-year period takes on the order of 120 additional cancer life-years a year. At between five and ten life-years lost per cancer case, that is roughly only 12 to 25 extra cases each year. Against the roughly 55,000 men diagnosed with prostate cancer in the UK each year, an increase of that size is under one twentieth of one percent. It too would not be detectable in any safety measure. The actual risk is measurable and significant at 24% when six trials were rexamined for prostate cancer risk.

The benefit is so small, and the exposed population so large, that only a fraction of an already-measured harm would remove it entirely. It is a scandal that the harm measure was totally omitted from the financial calculation.

A financial calculation standing in for a judgement

It is worth commenting on the weight given to finance over ethics and harm. The defence offered for all of this is that folic acid is cheap. The addition costs about 0.008 pence per loaf, and against a benefit expressed in hundreds of millions the measure looks unarguable. But finances are only a small part of what matters.

Fortification is not a treatment offered to a patient who consents. It is the medication of the entire population, 69 million people, through a staple food, most of whom are not pregnant, will never be pregnant, and gain nothing from the folic acid they will now eat in every loaf. Mass medication of the whole population through food crosses a red line ethically. There is no published assessment of the ethics of medicating a whole population without individual consent to benefit a few dozen.

There is also no risk-benefit assessment weighing the modelled gain against the known and potential hazards to others. The only assessment carried out was financial, and even that was the light-touch de minimis form, reserved for measures whose cost to business is judged too small to warrant a full one.

Conclusion

Mandatory folic acid fortification has been justified by a modelled claim that it will save 200 babies. The benefit is principally to pregnancies that would have ended in termination. Even accepting the government’s own modelling, the policy is expected to prevent only a few dozen neural tube defect-affected live births each year, of which about 28 would be children living with disability, while exposing the entire population to known and unknown harm.