Background: A highly soluble iron-casein complex has been developed for food fortification purposes with the aim to provide high iron bioavailability.
Objective: We aimed to determine the iron bioavailability of the iron-casein complex relative to that of ferrous sulfate (control) when given with whole milk in healthy young women.
Methods: A randomized comparator-controlled trial with a crossover design was conducted using the erythrocyte incorporation dual stable isotope (57Fe, 58Fe) technique. Iron absorption from the iron-casein complex was compared with that from ferrous sulfate in 21 healthy women aged 20-38 y with normal iron status.
Results: Fractional iron absorption (geometric mean; -SD, +SD) from the iron-casein complex (3.4%; 1.4%, 5.4%) and from ferrous sulfate (3.9%; 1.7%, 6.1%) were not statistically different (P > 0.05). The relative bioavailability value of the iron-casein complex to ferrous sulfate was determined to be 0.87 (-1 SD, +1 SD: -0.90, +2.64).
Conclusions: The iron-casein complex has iron bioavailability comparable to that of ferrous sulfate in healthy young women. This trial was registered at www.anzctr.org.au as ACTRN12615000690550.
Keywords: bioavailability; dual isotope; erythrocyte; iron; iron absorption; stable isotope; women.
Copyright © American Society for Nutrition 2019.