Further proof folic food fortification works
adding folic acid to food can dramatically reduce the incidence of
birth defects.
The study, published in BMC Pregnancy and Childbirth, showed that the proportion of babies born with neural tube defects in the province of Newfoundland and Labrador, Canada, dropped by 78 per cent after the Canadian government ruled that folic acid must be added to flour, cornmeal and pasta.
The researchers - led by Dr Catherine McCourt, from the population and public health branch of Health Canada - found that women of childbearing age who ate the fortified food increased their dietary intake of folic acid by an average of 70 micrograms a day. Their blood folate levels also increased significantly.
Since fortification in 1998, the incidence of neural tube defects in this province has reduced from an average of 4.36 defects per 1000 births to an average of 0.96 defects per 1000 births.
Moreover, during this period, the number of women aged between 19 and 44 who took folic acid supplements rose significantly from 17 per cent to 28 per cent.
However, the researchers were not able in this study to determine the separate contributions of food fortification and supplement use in the decline of neural tube defects.
The authors therefore concluded that: "public education regarding folic acid supplement use by women of childbearing age should continue."
Furthermore, they noted that they found no evidence during this study of a deterioration in vitamin B12 status in this age group and no evidence that improved levels of blood folate masked this vitamin deficiency, as some research has suggested.
Last week, NutraIngredientsUSA reported that a record number of American women of childbearing age were taking folic acid supplementation, according to a survey by a national health agency.
The March of Dimes, a voluntary health agency that aims to improve the health of babies by preventing birth defects and infant mortality, found that 40 percent of American women aged 18 to 45, took a daily multivitamin containing folic acid in 2004.
This was an increase of eight percent compared to last year and the highest level since the agency began its survey over 10 years ago.
"We're surprised at this increase, but it's good news," says Dr. Jennifer Howse, president of the March of Dimes. "It is especially important because we've been worried about the effects on mothers and babies of low-carbohydrate diets that drastically reduce grain foods enriched with folic acid, such as bread and pasta."
The survey revealed that 49 percent of women who have been on low-carb diets in the past six months had taken a daily multivitamin containing folic acid.
"Perhaps these women are taking their vitamins because they realize they're missing out on important food groups," said Dr Howse.
But, she ruled out the possibility that low-carb and other diets were the only reason behind the increase because at 39 percent rates of folic acid use were also higher than expected for women not dieting.
Of women who were not pregnant at the time of the 2004 survey, 37 percent reported taking a vitamin containing folic acid daily, up from 30 percent in 2003.
Morever, more women seemed to understand the importance of folic acid to the health of babies. A comparison with the eight previous surveys showed that 12 percent of women know that, to be effective, folic acid must be consumed before pregnancy. This figure was only two percent in 1995. Those who know that folic acid helps prevent birth defects increased to 24 percent in 2004, up from only four percent in 1995.
The US, Canada and Chile currently require folic acid fortification of flour to protect women from the risk of birth defects in their babies, shown to be at higher risk if the mother is deficient in this vitamin.
