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Updated: Oct 9, 2026

The Caco-2 Cell Bioassay for Measurement of Food Iron Bioavailability
Published on: April 28, 2022
An evaluation of EDTA compounds for iron fortification of cereal-based foods
R F Hurrell1, M B Reddy, J Burri
1Nestec Ltd, Nestlé Research Centre, Lausanne, Switzerland. richard.hurrell@ilw.agrl.ethz.ch
Abstract:
Fe absorption was measured in adult human subjects consuming different cereal foods fortified with radiolabelled FeSO4, ferrous fumarate or NaFeEDTA, or with radiolabelled FeSO4 or ferric pyrophosphate in combination with different concentrations of Na2EDTA. Mean Fe absorption from wheat, wheat-soyabean and quinoa (Chenopodium quinoa) infant cereals fortified with FeSO4 or ferrous fumarate ranged from 0.6 to 2.2%. For each infant cereal, mean Fe absorption from ferrous fumarate was similar to that from FeSO4 (absorption ratio 0.91-1.28). Mean Fe absorption from FeSO4-fortified bread rolls was 1.0% when made from high-extraction wheat flour and 5.7% when made from low-extraction wheat flour. Fe absorption from infant cereals and bread rolls fortified with NaFeEDTA was 1.9-3.9 times greater than when the same product was fortified with FeSO4. Both high phytate content and consumption of tea decreased Fe absorption from the NaFeEDTA-fortified rolls. When Na2EDTA up to a 1:1 molar ratio (EDTA:Fe) was added to FeSO4-fortified wheat cereal and wheat-soyabean cereal mean Fe absorption from the wheat cereal increased from 1.0% to a maximum of 5.7% at a molar ratio of 0.67:1, and from the wheat-soyabean cereal from 0.7% to a maximum of 2.9% at a molar ratio of 1:1. Adding Na2EDTA to ferric pyrophosphate-fortified wheat cereal did not significantly increase absorption (P > 0.05). We conclude that Fe absorption is higher from cereal foods fortified with NaFeEDTA than when fortified with FeSO4 or ferrous fumarate, and that Na2EDTA can be added to cereal foods to enhance absorption of soluble Fe-fortification compounds such as FeSO4.
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