NaFeEDTA Improves Iron Absorption from High Extraction Wheat Flour in Pakistan as Assessed by Stable Isotope Techniques

Abstract

Objectives: Evaluation of iron absorption from iron fortified wheat flour at  fortification levels below international recommendations (10 ppm) in presence of different EDTA levels to improve iron absorption. Methods: Two iron absorption studies from chapatti based, vegetarian meal were conducted in non-anaemic adolescent girls (n=20/19). Chapattis were prepared from wheat flour fortified with labelled iron (57Fe/58Fe) to which EDTA was added at two different molar ratios (Study 1: EDTA at  molar ratio 1:1 relative to fortification iron (NaFeEDTA); Study 2: EDTA at increased molar ratio of EDTA to iron of 1:1 relative to total iron in wheat flour (NaFeEDTA+EDTA). Iron absorption from meals prepared with EDTA (meal B, 58Fe) was compared to absorption from meals with FeSO4 (meal A, 57Fe) using randomized cross-over design in same subjects. Iron absorption was determined by quantification of amount of isotopic labels incorporated into erythrocytes 14 days after test meal administration Results: In study 1, 57Fe absorption (A) was *4.1% (2.6%, 6.5%) while 58Fe absorption(B) was *9.1% (5.6%; 14.8%). In study 2, 57Fe Absorption (A) was *5.4% (3.5%, 8.5%) while 58Fe absorption (B) was *220.1% (10.1%, 40.0%) Absorption ratio B/A in Study I was *2.2 (1.65; 2.98) and in Study II was 3.70 (2.43, 5.65). *geometric means (-SD, +SD) Conclusions: EDTA increased iron absorption significantly in both studies (p<0.001). When wheat intake is high in target populations, lowering iron fortification levels while increasing EDTA content, or adding EDTA alone, can be considered an alternative fortification strategy.