EDTA and the absorption of iron from food.

Iron EDTA is an effective fortificant in meals of low iron bioavailability. Na2EDTA, added to food to prevent oxidation, enhances iron bioavailability by chelating added iron. This study examines the optimal ratio of EDTA to iron causing enhanced iron absorption. Iron absorption from a rice-based meal of low iron bioavailability containing increasing molar ratios of EDTA to iron, was compared in 127 women volunteers by using standard double isotope techniques. Iron deficiency was present in 38% of the women. Mean standardized absorptions, at EDTA-iron ratios of 0.25, 0.5, and 1, were 11.3%, 13.5%, and 8.8%, respectively, compared with 3.8% when no Na2EDTA was present. In meals of high iron bioavailability, Na2EDTA (EDTA:Fe, 1.0) produced little enhancement (potato-based meal) nor inhibited iron absorption (apple-based meal). Na2EDTA added to meals with molar ratios of EDTA to iron between 1.0 and 0.25 significantly increases iron absorption provided the meal is of low iron bioavailability.