Iron Absorption from Two Milk Formulas Fortified with Iron Sulfate Stabilized with Maltodextrin and Citric Acid

Abstract

Background: Fortification of milk formulas with iron is a strategy widely used, but the absorption of non-heme iron is low. The purpose of this study was to measure the bioavailability of two iron fortified milk formulas designed to cover toddlers’ nutritional needs. These milks were fortified with iron sulfate stabilized with maltodextrin and citric acid. Methods: 15 women (33–47 years old) participated in study. They received on different days, after an overnight fast, 200 mL of Formula A; 200 mL of Formula B; 30 mL of a solution of iron and ascorbic acid as reference dose and 200 mL of full fat cow’s milk fortified with iron as ferrous sulfate. Milk formulas and reference dose were labeled with radioisotopes 59Fe or 55Fe, and the absorption of iron measured by erythrocyte incorporation of radioactive Fe. Results: The geometric mean iron absorption corrected to 40% of the reference dose was 20.6% for Formula A and 20.7% for Formula B, versus 7.5% of iron fortified cow’s milk (p < 0.001). The post hoc Sheffé indeed differences between the milk formulas and the cow’s milk (p < 0.001). Conclusion: Formulas A and B contain highly bioavailable iron, which contributes to covering toddlers’ requirements of this micronutrient.

Comparative assessment and suitability of iron and the nutritional composition of fortified foods for young children

“…The addition of vitamin C at 2:1 or 4:1 molar ratio enhanced iron absorption by a factor of 2-4 and greatly compensated for the inhibitory effect of calcium on iron absorption in a dose-dependent manner (Walczyk et al, 2014). Similar findings were also reported on the effect of vitamin C on iron absorption in the presence of calcium using iron-fortified milk formulas (Pizarro et al, 2015) and RTE breakfast cereals (Garcia-Casala et al, 2003). Therefore and based on the above argument, a deep insight into the data presented in Table 2 reveal that malted milk drinks and milk powder formulas contain vitamin C to iron in a ratio of 3:1 and 8:1 respectively.…”

Iron Deficiency Anemia in Children

“…It is important to emphasize that only a fraction of dietary iron is absorbed from food, depending on bioavailability (dietary iron absorption). Human milk contains only 0.3-1.0 mg/l of iron, but the bioavailability of iron is 50%, while milk formulas contain 12 mg/l of iron with bioavailability of iron 4-6% only [42]. As mentioned above, dietary iron has two main forms: heme and nonheme iron.…”

Challenges and strategies to combat global iron deficiency by food fortification

“…Ferric chloride 10, 20, and 40 mg Fe/kg yogurt (Hekmat and Mahon, 1997) Milk Ferrous sulfate 1.2 mg Fe/100 ml milk (Pizarro et al, 2015) Sugar NaFeEDTA 1 g Fe/kg sugar (Viteri et al, 1995) Salt Ferrous sulfate 1 mg Fe/g salt (Rao, 1994) Bread rolls FeSO 4 and NaFeEDTA 2.5 mg Fe/50 g wheat flour (Hurrell et al, 2000) Infant cereal…”