Baroness Gerada has sent a detailed reply
On 30th August, Nick Hunt from the Perseus Group, joined Clare Craig from HART and Liz Evans from UKMFA in writing to the 20 medically qualified MPs and peers about the potential risks of mandatory folic acid supplementation of the entire population of men, women and children, all for the purported benefit to a tiny number of women in very early pregnancy. Our full letter is here and the reply from Baroness Gerada below.
In fairness, it is much more thorough than the previous reply from the Secretary of State (or rather her Correspondence Officer).
From: GERADA, Baroness <[email protected]>
Thank you for writing to me about the Government’s decision to require the fortification of non-wholemeal wheat flour with folic acid.
I have read the concerns you raise carefully.
I am afraid that I do not share your conclusion that the policy should be reversed.
I accept that there are legitimate issues that merit continuing surveillance, including the relationship between high folate status and vitamin B12 deficiency, the presence of unmetabolised folic acid after consumption, and the effects of excessive folic acid intake. However, the existence of a plausible mechanism or an observational association is not itself evidence that fortification at the level adopted in the United Kingdom causes clinically important harm.
That uncertainty must be weighed against strong and consistent evidence of benefit. Folic acid taken around conception reduces the risk of neural tube defects, including spina bifida and anencephaly. This is not simply a theoretical benefit. A 2026 systematic review and meta-analysis of 14 studies, encompassing more than 33 million people, reported that mandatory fortification was associated with a 44% reduction in neural tube defects (Moges et al., 2026). Canadian population data recorded a fall from 1.58 to 0.86 neural tube defects per 1,000 births after fortification, a reduction of 46% (De Wals et al., 2007).
The United Kingdom measure is deliberately calibrated. The regulations require 250 micrograms of folic acid per 100 grams of non-wholemeal common wheat flour, and the Government’s modelling estimates a 15% to 22% reduction in neural tube defects at that level. The existing advice that women who may become pregnant should take 400 micrograms daily before conception and during the first 12 weeks of pregnancy remains in place. Fortification supplements that advice; it does not replace it (Department of Health and Social Care, 2024a; 2024b).
I am also not persuaded by the argument concerning common MTHFR variants. Such variants can alter folate metabolism, but they do not mean that a large proportion of the population is unable to process folic acid. The United States Centers for Disease Control and Prevention states that people with common MTHFR variants can process folic acid and that folic acid intake has a greater influence on blood folate than genotype. Even among people with the 677TT genotype, average blood folate is about 16% lower at a comparable intake, and folate concentrations still rise in response to folic acid (CDC, 2026a).
The concern about vitamin B12 deficiency deserves more serious consideration. Historically, high doses of folic acid could correct the anaemia of B12 deficiency while neurological disease continued.
That is a reason for clinical vigilance, reliable diagnosis and post-implementation monitoring, especially in older people. It is not, in my view, sufficient reason to reject a carefully dosed intervention with a well-established capacity to prevent serious congenital abnormalities. Modern diagnosis is not dependent on macrocytosis alone, and B12 status can be investigated directly.
Similarly, unmetabolised folic acid can be detected in the blood, but detection is not synonymous with toxicity. The CDC’s current evidence review states that no confirmed health risk has been demonstrated from unmetabolised folic acid at recommended exposures (CDC, 2026b).
On cancer, an individual-participant meta-analysis of 13 randomised trials involving 49,621 people found no significant increase in overall or site-specific cancer during an average of 5.2 years of treatment, generally at doses higher than those obtained through flour fortification (Vollset et al., 2013).
Nor do I regard food fortification as equivalent to indiscriminate “mass medication”. Non-wholemeal flour in the UK has long been fortified with calcium, iron, thiamin and niacin. Folic acid is being added to that established public-health framework. Ingredient labelling is required, while unfortified choices, including wholemeal flour and other grains, remain available (Department of Health and Social Care, 2021).
The practical case for a population measure is important. Neural-tube closure occurs very early, often before pregnancy is recognised. Relying solely on individual supplementation therefore misses some women with unplanned pregnancies and those least likely to receive or act on preconception advice. Australian evidence is instructive: after mandatory fortification, neural tube defects among Aboriginal Australians fell by 68%, helping to narrow a marked health inequality (Bower et al., 2016).
No population-health intervention should be exempt from evaluation. I would support continued monitoring of neural tube defects, folate and B12 status, excessive total intake and any credible adverse signals after implementation. But policy should be determined by the balance and magnitude of the evidence, not by treating every theoretical risk as though harm had already been established.
Having considered the concerns raised, I believe that appropriately dosed folic-acid fortification is a proportionate, evidence-based measure likely to prevent serious and avoidable harm.
Thank you again for taking the trouble to write to me.
I am copying in Lord Rooker given his long standing interest in this area
Yours sincerely,
Baroness Gerada
Bower C, Maxwell S, Hickling S, D’Antoine H, O’Leary P. Folate status in Aboriginal people before and after mandatory fortification of flour for bread-making in Australia. Aust N Z J Obstet Gynaecol. 2016;56(3):233-237. doi:10.1111/ajo.12425. Available online
Centers for Disease Control and Prevention (CDC). MTHFR Gene Variant and Folic Acid Facts. Updated 16 July 2026. Available online
Centers for Disease Control and Prevention (CDC). Folic Acid Safety, Interactions, and Health Outcomes. Updated 15 July 2026. Available online
Department of Health and Social Care. Proposal to add folic acid to flour: consultation response. 20 September 2021. Available online
Department of Health and Social Care. Summary of responses and government response: amending the Bread and Flour Regulations. 17 January 2024. Available online
Department of Health and Social Care. Birth defects prevented by fortifying flour with folic acid. 14 November 2024. Available online
De Wals P, et al. Reduction in neural-tube defects after folic acid fortification in Canada. N Engl J Med. 2007;357:135-142. doi:10.1056/NEJMoa067103. Available online
Moges S, et al. The effectiveness of mandatory folic acid fortification compared with pre-fortification periods on reducing neural tube defects: a systematic review and meta-analysis. BMC Nutrition. 2026. PMID:41526993. Available online
Vollset SE, et al. Effects of folic acid supplementation on overall and site-specific cancer incidence during the randomised trials: meta-analyses of data on 50,000 individuals. Lancet. 2013;381:1029-1036. doi:10.1016/S0140-6736(12)62001-7. Available online
cc: The Rt Hon. the Lord Rooker
