The UK is moving towards making addition of folic acid to flour or bread mandatory in order to reduce the number of babies born with severe disabilities.
After lengthy public consultations the Food Standards Agency (FSA) has said that it would approach the Government with its recommendations next month after it decides whether folic acid should be added to flour or to bread.
If ministers accept the FSA's proposals, it will be the first time since the end of the Second World War that manufacturers in Britain are ordered to add vitamins to food. In 40 other countries including USA, Chile and Canada folic acid enrichment of flour is insisted on.
Members of the FSA board said there was "strong evidence" that fortifying bread or flour would lead to a major reduction in the 700 to 900 babies born each year with neural tube defects like spina bifida.
Neural tube defects are serious birth defects with symptoms that range from mild to severe impairment. They are caused by incomplete development of the brain, spinal cord and/or their protective coverings. This occurs when the fetus' spine fails to close properly during the early stages of pregnancy.
It is generally recommended that women who are trying to become pregnant, or are already pregnant, should take a 400 microgram supplement of folate, a water-soluble B vitamin until at least the 12th week of pregnancy to cut the risks of neural tube defects in their babies.
Folate is a vitamin found in broccoli, sprouts, peas, chickpeas, brown rice and fruit. Folic acid is its synthetic form.
It is important for the development of the spine in the first stages of pregnancy and women are advised to eat extra folic acid when trying to get pregnant.
However, research suggests that only half of such women adhere to this advice.
Also, up to half of pregnancies are unplanned, meaning women may miss the opportunity.
Countries which introduced mandatory fortification have seen defect rates decline by up.
The evidence has prompted the FSA board to agree to the measure after rejecting it five years ago.
But critics argue that fortifying bread amounts to "mass medication", denies consumers choice and creates health problems because folic acid makes it difficult to identify vitamin B12 deficiency in older people, a condition that can damage the nervous system.
It was largely because of concerns about B12 deficiency that the FSA board rejected the idea of fortification five years ago. There are also fears that fortification could cause difficulties for bakers and raise the price of bread.
To minimise health risks, the FSA said it would introduce controls on the voluntary fortification of foods such as breakfast cereals, and guidance on folic acid supplements. It would also exclude wholemeal flour and bread from the programme to leave people with a choice.
Dame Deirdre Hutton, the chairman of the FSA's board, said that fortification would have health benefits for the population.
The FSA's decision was widely welcomed by health charities, including the Association for Spina Bifida and Hydrocephalus, which said about 85 per cent of pregnancies affected by neural tube defects ended in abortion.
Andrew Russell, its chief executive, said: "We look to health ministers to speedily implement this life-saving measure."
But a critic wanted to know, "Has any investigation been made into the effects of folic acid on the correct working of other medications? The Pfizer medicines compendium states that folic acid may decrease phenytoin serum levels. These levels are important for those people who use the anti convulsant drug Epanutin to control their epilepsy."
And there was this comment on the internet: I am a 67 year old man so my chances of having a baby with birth defects are remote, why should I have this genetically modified bread imposed upon me? it tastes like cardboard now with all the long life additions etc. Why not leave things as they are and market the modified bread to people who want it.
Andrew Lansley, the shadow health secretary, also noted important questions remained unanswered.