A problem with diet

Study shows why Newfoundland women have so many babies with neural tube defects

by Sharon Gray

At least 20 per cent of Newfoundland women don't get enough folic acid in their diet, putting them at risk of having a baby with a neural tube defect such as spina bifida.

A study by Dr. James Friel, Biochemistry, Dr. Elizabeth Ives, Genetics, and Dr. Sam Ratnam, Public Health, confirms what has long been known: the Newfoundland diet does not provide adequate levels of folic acid. The number of babies born with neural tube defects in the province is about five in 1,000, the highest rate in Canada (the average rate in North America is one per thousand).

Foods high in folic acid include orange juice, asparagus, broccoli and leafy green vegetables such as spinach and turnip greens. Women of childbearing age need to get about 600 micrograms of folic acid daily, but the average diet in Newfoundland provides only about 200 micrograms.

The study analysed blood samples from 1,400 pregnant women from four hospitals in three regions of the province. By measuring the folate levels in red blood cells, the researchers determined that about 11 per cent of these women were clinically deficient with folate rates less than 148 nanogram/ml, and another 12 per cent had indeterminate levels from 148-186 nanogram/ml.

Dr. Ratnam said this deficiency was higher among women in the age bracket 14-24 years than in those over 24 years. He stressed that adequate folate levels are critical during the first few weeks of conception.

"Basically more than 20 per cent of the pregnant women in our study had poor folate status at the time of conception," said Dr. Friel. "Even more may be at risk, because some are in a grey area where their folate levels are not ideal. We know that the lower a woman's folate level is, the higher the risk is of having a baby with a neural tube defect."

Trials in England and Hungary have proved that folic acid supplementation is very effective in preventing neural tube defects. In the United States, flour has been fortified with folic acid as of Jan. 1, 1998.

At a meeting of Canadian health ministers in March 1995, plans were developed for a pilot project that would fortify flour in Newfoundland with folic acid. In preparation for that project, Drs. Friel, Ives and Ratnam went ahead with a study to get baseline values. This study was supported financially by the Janeway Research Foundation.

Dr. Ives said it now seems probable that Canada will soon be fortifying cereals with folic acid, just like the U.S.A. "In view of this, the federal department of health plans to conduct additional baseline studies in some other population groups."

But even if cereals and flour are fortified with folic acid, it will not completely solve the problem. Women of childbearing age should get about 600 micrograms of folic acid daily, and fortification would only add about 100 micrograms to the average intake of 200.

Dr. Friel said the only answer is to take supplements. "As pregnancies are unplanned in many instances, women with this potential should always take supplements."

Most multi-vitamin pills contain 400 micrograms of folic acid, so a vitamin pill a day is sufficient for most women. However, women with a family history of neural tube defects or who are on oral contraceptives or anti-epileptic drugs need much more than this and they should consult their physician for an appropriate prescription.

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