Folic acid cut birth defect rate in Canada - study

BOSTON, July 12 (Reuters) The Canadian government's order to add folic acid to most cereal products has cut the number of neural tube birth defects in half, according to a study published here.

The research team led by Philippe De Wals of Laval University in Quebec found that the rate of these major defects in newborns fell from 0.158 per cent before folic acid fortification became mandatory in 1998 to 0.086 per cent afterward.

''Marked reductions in rates of neural-tube defects have occurred across Canada after fortification of food with folic acid was implemented,'' the researchers wrote in their report, published in the New England Journal of Medicine.

Adding folic acid to food has been shown to prevent neural tube defects, which occur when the neural tube, which later turns into the brain and spine, fails to form properly in the womb. This takes place within the first weeks of a pregnancy, often before a woman knows she is pregnant.

Spina bifida and anencephaly are the two most common neural tube defects.

The provinces where the rates of neural tube defects were highest before fortification took effect showed the biggest decline in neural tube defects once the cereals were treated with the B vitamin, the researchers found.

''After full implementation, geographical differences in rates almost disappeared,'' they wrote.

The United States began requiring fortification of white flour, cornmeal, pasta and breakfast cereals at the beginning of 1998, 11 months before Canada's rules took effect.

SHARP DROP IN 1998 The study found that the rate of defects was stable from 1993 to 1995. It peaked in 1996, although that may have been a random increase.

The rate dropped in 1997 to 1993-1995 levels, then dropped sharply in 1998 and declined for the two subsequent years. From 2000 to 2002, the final year of the study, the levels remained low.

''Distribution of fortified food started at the beginning of 1997, and by the end of that year, the entire milling industry had adopted fortification in anticipation of the coming mandatory requirements in the United States and Canada,'' the researchers wrote.

Of the remaining defects, most continue to be spina bifida, where the backbone of the fetus does not properly close around the spinal cord. But that condition seems to be making up a smaller share of the defects after fortification.

Before cereal products were treated, doctors were advising pregnant women to take folic acid supplements to reduce the risk of neural tube defects. But the recommendation had little effect on the birth defect rate, probably because women were not taking supplements, according to previous studies in Quebec.

REUTERS AE BST0846