Evaluation of Food Fortification with Folic Acid for the Primary Prevention of Neural Tube Defects

Conclusions

Primary findings

• The implementation of food fortification with folic acid has been accompanied by a marked decrease (78%) in the incidence of NTDs in Newfoundland. Increased use of folic acid supplements may also have played a role in the declining NTD rate. It was not possible to determine the separate contributions of fortification and supplementation.

• At the current levels of food fortification with folic acid, there is no evidence of a deterioration in vitamin B₁₂ status among seniors. Furthermore, there is no evidence of improved folate status resulting in masking of the haematological manifestations of vitamin B₁₂ deficiency among seniors as a group.

Secondary findings

• Although there has been an increase in women's knowledge and use of folic acid supplements, in Phase II of our study only about one-half of the women of childbearing age were aware of the importance of folic acid. Approximately one-third were taking supplements containing folic acid in Phase II.

• The results of this study highlight the need to re-examine strategies for improving women's understanding of the link between periconceptional folic acid intake and NTD prevention.

• As a result of fortification, there have been significant improvements in blood folate status among women of childbearing age and seniors.

Recommendations

• Continue food fortification with folic acid at currently mandated levels.

• Continue public health efforts to promote awareness of the importance of folic acid supplementation by women of childbearing age. Initiate studies to quantify the independent contribution of fortification and supplementation to rates of NTDs.

• Continue monitoring of possible adverse health outcomes of fortification, particularly in seniors and children.

• Assess changes in NTDs post fortification in areas with lower incidence rates.