Researchers have discovered a link between increased levels of the B vitamin folic acid in a woman’s diet and a reduction in the number of babies born with severe congenital heart defects. A McGill University study found a six percent decline in cases of congenital heart defects in the province of Quebec after 1998 – the year Canada began requiring food companies to enrich flour and pasta products with folic acid.

The authors, whose paper was published in the British Medical Journal in May of 2009, claim their results are not likely mere coincidence, since the timing of the decline coincides exactly with the introduction of mandatory fortification. And most other factors known to boost the risk of heart defects in babies – among them older maternal age, medication use and obesity – gradually increased over the study period, but the decline in heart defects still declined.

More research is needed to prove that adequate levels of folic acid in pregnant women will prevent congenital heart defects and what daily dosage is required. Previous research has indicated that many pregnant women are deficient in folic acid.