The Effect of Folic Acid Fortification on Folate Intake in Rural Women

Abstract

The objective of this study was to determine the effect of fortification on dietary folate intake in a sample of rural women. The 289 subjects were recruited at 2 community health screenings. Most were white (88%), college educated (51%), and middle income (60% with incomes $30K+). Average age was 47.7 years. Dietary assessment data were collected with a quantitative food frequency (Block) using the Nutrition DISCovery™ program. Fortification was simulated using the fortification standard, i.e., 140μg folic acid/100g flour. Mean dietary intake of folate increased significantly with fortification (320 vs 489μg, P<.001). Women in the lower quartiles for age (18-39 & 40-46y) consumed more servings from the bread group than women in the upper quartile (55-89 y). Thus, the improvement in folate intake for the younger women was significantly greater than older women (P=.003). On the other hand, the upper quartile women consumed significantly more servings of fruits (P<.001) and vegetables (P=.037) than women in the lowest quartile; food groups contributing to folate intake, but unaffected by fortification. The proportion of women consuming the dietary reference intake (DRI) of 400ug from food increased by 40% after fortification. From food alone, 35% of the women were still not meeting the DRI; this decreased to 20% when taking folic acid supplements into account. Concerns have been expressed that fortification may elevate folate intakes to unsafe levels (≥1000μg). Of the 10% of women meeting this criterion after fortification, their intakes ranged from 1009-1300 μg or levels that would preclude undue concern. Most of these women were taking a daily supplement of 400ug. The improvements in folate intake in this sample may not apply to groups with limited resources. Based on this sample of highly educated, adult women, the current level of fortification will improve the intakes of a large proportion of women especially when accompanied with folic acid supplements. However, some women still did not meet current recommendations.