The Food Standards Agency in the UK is recommending the addition of the vitamin folic acid to all flour and bread on sale in Britain within the next year.
The agency will recommend in principle that in future all brown and white flour be fortified with folic acid.
Wholemeal bread will not require additional folic acid.
Calcium, iron, thiamine and niacin are already compulsory ingredients in white or brown flour.
There is an abundance of research in Britain, Canada and the US showing the importance of folic acid in preventing babies being born with spina bifida and brain defects and the medical profession has known for some time that women who take the vitamin at the start of their pregnancy can avoid the defect which affects between 700 and 900 pregnancies in Britain every year.
It seems however that large numbers of women are not following the advice to take folic acid in order to reduce the chance of their babies being born with neural tube defects including spina bifida.
Now experts believe that folic acid may also prevent strokes, bone disorders and heart disease in the whole population.
The recommendation was first suggested ten years ago but was rejected in 2003 by the food watchdog by one vote, due to concern that the fortification of food would mask cases of vitamin B12 deficiency among the elderly.
Since such concerns have proved largely unfounded the Food Standards Agency now recommends in principle the fortification of all brown and white flour with folic acid.
The move will be the first time since the Second World War that manufacturers have been ordered to add nutrients to food on the ground of public health.