Flour fortification with folic acid in Chile. Unintended consequences

Background: High daily intake of folic acid (FA) could determine health risks in some populations. Aim: To review the Chilean FA wheat flour fortification and to identify the existence of populations at risk. Material and Methods: We categorized the FA levels in flour samples (percentil P) (2005-2008) and estimated intake of FA (mg/d) in adults from apparent bread consumption according to different levels (P20, 50 and 95) and children consumption (8-13 years) considering socioeconomic status (SES), bread/g/d intake (P20, 50 and 75) and regulated level of flour fortification (2.2 mg FA/100 g). Daily Dietary Folate Equivalent (DFE) consumption was estimated from serum folate in adults and elderly people (both sexes). We calculated the percentage of population with FA intakes over the estimated average requirement (EAR) and maximum level (UL) pre and post-fortification. Results: There is great variability in FA flour: 10-20% samples without FA and 10-30% with levels > 2.2 mg/100 g. Adult daily consumption (2-4 day/loaves) could determine FA intakes close to UL. Children daily bread consumption (low socioeconomic level) > P75 have intakes close to UL. Post-fortification estimated daily DFE from serum folate in women, men and elderly people show: 99% of women, 100% of men and the elderly people have intakes higher than EAR. Additionally 2.3% of women and 6% of men would have intakes near the UL. Conclusions: The flour FA levels and serum folate levels in some populations show increased FA post-fortification intakes, which could lead to greater risk suggesting a revision of the fortification level. (Rev Med Chile 2010; 138: 832-840).