Mandatory¹ fortification of bread with folic acid would slash² the risk of babies being born with a heart problem, experience from Canada shows.

加拿大研究表明，面包里强制加入叶酸可降低新生儿的心脏问题。

Flour can be fortified³ with folic acid

Rates of severe congenital（天生的，先天的） heart defects among newborns in Quebec fell significantly after the move to fortify⁴ flour and pasta（生面团） began in 1998.

The British Medical Journal online study lends support to calls for introducing fortification to Europe.

But others argue against this, saying it would inevitably⁵ harm some people.

The fear is that adding folic acid to products like bread could harm some elderly people if they are deficient⁶ in other B vitamins.

In extreme cases, this can cause irreversible（不可逆转的） damage to the nervous system.

There is also concern that it may also increase the risk of certain cancers, including bowel⁷（肠） cancer, in some people.

In 2007 the UK's watchdog, the Food Standards Agency, agreed with expert recommendations to fortify bread or flour with folic acid.

Since then, at the request of the Chief Medical Officer, an expert working group on folate（叶酸） has been considering the results of recent trials looking at the effect of folic acid on the risk of some types of cancer.

The group is expected to report back to Sir Liam Donaldson this summer.

Risk reduction

Folic acid is a synthetic⁸（合成的，人造的） form of folate, a B vitamin found in a wide variety of foods including liver and green leafy vegetables.

Pregnant women and those trying to conceive（构思，怀孕） are already advised to take folic acid supplements to reduce the risk that their baby will have a "neural⁹ tube（神经管）" birth defect like spina bifida（脊柱裂）.

But uptake（摄取，领会） is not ideal, particularly because some pregnancies¹⁰ are unplanned and can go unnoticed for some weeks.

The latest work suggests folic acid also cuts the risk of baby heart defects.

In the seven years after fortification（防御工事） was introduced there was a 6% drop per year in the birth prevalence（传播，流行） of severe heart defects.

This compares with a 9% drop in neural tube defects.

Writing in the BMJ, lead author Professor Louise Pilote of McGill University in Montreal, said: "Given that severe congenital heart defects require complex surgical¹¹ interventions¹² in infancy¹³ and are associated with high infant mortality rates, even a small reduction in the overall risk will significantly reduce the costs associated with the medical care of these patients and the psychological burden on patients and their families."