Usable folate can run short in the embryo while the mother’s blood folate reads entirely normal Dr Clare Craig This article attempts a synthesis of the science on neural tube causation. Key points A mandate to add folic acid to flour depends on three beliefs: ● that these defects arise because women do not get enough […]
Author: Clare Craig
A country wide experiment with no way to collect the results
A fall, a plateau or a rise in neural tube defects could all be presented as success Dr Clare Craig Key points Folic acid is being added to non-wholemeal wheat flour with a mandate for all companies beginning on 13 December 2026. HART are opposed to this mandate. If it goes ahead, there are serious […]
How folic acid works
A mechanism was traced for the first time in July 2026 Dr Clare Craig There is only one trial of ordinary women given a lower dose of folic acid in pregnancy and it showed nine pregnancy losses for each prevented neural tube defect. For high risk women, thirty years after trials showed that folic acid […]
What can we learn from neural tube defects in migrants?
Why do Bangladeshi and Pakistani mothers in England have such different rates of NTDs? Dr Clare Craig Key points The rates before migration Pakistan does not have national birth defect surveillance but where rates of neural tube defects have been estimated they are high. A systematic review of worldwide incidence found five studies from Pakistan […]
Case studies in neural tube defect causation
Neural tube defects occur in epidemic waves. Why? Dr Clare Craig Key points There is a firm belief that it is folate deficiency that leads to neural tube defects. This is despite a lack of evidence of deficiency and the established effects of famine. Because of this belief other questions do not get asked about […]
What caused Britain and Ireland’s neural tube defect epidemics?
The search for the reason was abandoned halfway through Dr Clare Craig Britain and Ireland once carried the highest recorded rates of neural tube defect in the world. They no longer do. The rates rose for 60 yrs, peaked twice and then collapsed and neither the rise nor the fall has been explained. If we […]
Three things high folic acid does to animals
Animal models provide evidence of harm Dr Clare Craig Rodents handle folic acid far more efficiently than humans but nevertheless they see three clear types of harm: altered brain development, weakened immune defence and faster growth of tumours that already exist. There is twenty five years of evidence on these topics. Most of the evidence […]
The enzyme bottlenecks
MTHFR gets the attention but DHFR is slow in everybody. Dr Clare Craig Ask why folic acid might be a problem and the conversation arrives at MTHFR within a few minutes. Have you been tested? Do you carry the variant? Should you be taking methylfolate instead? There is actually another gene that we should be […]
The plateau in four countries
Why is the decline that stopped in four countries cited as proof that folic acid worked? Dr Clare Craig Key points In every country cited as evidence that folic acid policy worked, neural tube defects had been falling for decades before the policy arrived. The decline did not accelerate when recommendations or fortification began. In […]
The impossible shop
Try buying a week’s food without folic acid. Dr Clare Craig Key points. From 13 December 2026 almost all non-wholemeal wheat flour must contain folic acid, and mills have been legally able to start adding it since Autumn 2024. Asked to let people opt out, the Government replied that individuals can “avoid fortified flour if they choose […]
Folic acid is in the food but not on the label
The government said it would tolerate the law being broken. Dr Clare Craig Mandatory folic acid fortification of non-wholemeal wheat flour does not come into force until 13 December 2026 but folic acid has been in the food supply for some time without anyone being informed. Millers began fortifying flour in September 2025 and by […]
Where is the safety trial on folic acid?
Eighty thousand people have been included in trials for benefit but none in a trial designed to question safety Dr Clare Craig Key points• At least thirty randomised trials involving 82,334 people have tested whether folic acid prevents heart disease and stroke. No trial has been designed to test whether it causes harm.• The safety evidence that […]
The statistical mistake that made it look like folic acid worked
The Canadian result survives even when every province is given the wrong outcome Dr Clare Craig Key pointsOne paper from Canada claims a 46 percent fall in neural tube defects after folic acid was added to flour. It also claims that the provinces with the highest rates before folic acid saw the biggest falls and […]
Why does bowel screening almost always expand when folic acid is rolled out?
Multiple countries increased bowel screening at a time when measuring any change from folic acid is really important Dr Clare Craig The first trial to raise a question about bowel cancer risk from folic acid found an increased risk of pre-cancerous growths called polyps. A small proportion of these progress to cancer over years. Bowel […]
Folic acid and heart stents
What is the evidence? Dr Clare Craig There has never been a trial designed to determine the safety of folic acid at any dose, let alone specifically focused on fortification doses. The evidence that exists is always second hand from trials designed to show a benefit; includes other vitamins alongside folic acid and uses doses […]
Canada’s 46 percent
What does the study with the most ambitious claim show? Dr Clare Craig Key pointsCanada claims the highest reduction in neural tube defects from folic acid fortification anywhere in the developed world – 46 percent. The United States with a near-identical programme claimed only 19 to 28 percent.The 46 percent comes from one study with […]
Why did Britain choose 250 micrograms of folic acid?
The model behind the mandate Dr Clare Craig Multiple countries have already added folic acid to their food but the decisions differ in terms of the dosage and the types of food affected. Country Minimum Maximum What the law covers Can it be avoided? United States 154 µg/100 g none only flour and grain products […]
The fall before folic acid
Neural tube defects in England and Wales fell dramatically from the 1960s to around 1990 then plateaued. Why? Dr Clare Craig Key points Total NTD pregnancy prevalence in England and Wales fell from 3.7 per 1,000 births in 1964 to 1.6 per 1,000 in 1990, a fall of 57 percent. From 1990 to 2004 the […]
