London, May 17 - British food experts agreed on Thursday that folic acid should be routinely added to either flour or bread in an attempt to reduce birth defects.
The Food Standards Agency's board, a government body designed to protect the public's health and consumer interests in relation to food, voted unanimously to back mandatory fortification.
But it decided that more research should be carried out into whether folic acid, a synthetic compound of vitamin B, should be added to just bread, or to flour, which would mean it would also go into flour-based products like cakes and biscuits.
The FSA board will discuss the details, along with other practical matters such as labeling, at its next meeting in June before making a final recommendation to the government.
Critics of compulsory fortification say it could present difficulties for bakers, push up the price of bread and quash consumer choice.
They also say folic acid may hide vitamin B12 deficiencies among the elderly.
But FSA board members decided the benefits outweighed the concerns.
It believes that babies born to women who take folic acid ahead of pregnancy will be less prone to neural tube defects (NTDs) such as spina bifida.
Between 700 and 900 pregnancies are affected by NTDs in the UK every year, and the agency said up to 160 cases a year could be prevented.
The FSA said the current policy of advising women to eat extra folic acid when trying to get pregnant has limited effectiveness because about half of pregnancies are unplanned.
Dame Deirdre Hutton, chair of the FSA's board, said the move "will help prevent birth defects in pregnancy and have wider health benefits for the rest of the population."
Dr Patricia Hamilton, president of the Royal College of Paediatrics and Child Health, welcomed the decision, saying the college "strongly believes that the addition... is in the best interests of children and young people".
The FSA board also agreed to recommend a series of controls if compulsory fortification is adopted, such as wholemeal flour being exempt, offering consumers more choice, clear labeling, monitoring and controls against possible risks such as cancer.
Controls on voluntary fortification, on products such as breakfast cereals and spreads, are also an essential part of its recommendation, it added.
If made compulsory, the UK will be following the U.S. which started fortifying flour with folic acid about 10 years ago. Sine then, it has seen a drop of more than a quarter in such birth defects.
Other countries including Canada, Australia, Mexico and Chile have followed their example.