The Effect of Human Milk Oligosaccharides and Galacto-oligosaccharides on Iron Absorption in Kenyan Infants

Effective and safe strategies to deliver iron to infants and young children in Sub-Saharan Africa are urgently needed. One potential strategy to improve safety of iron fortification is to limit the total amount of unabsorbed iron entering the colon by lowering the daily iron dose but at the same time ensure efficacy by maximizing absorption from this lower dose. In Kenyan infants, the investigators have recently shown that consumption of 7.5 g of the prebiotic galacto-oligosaccharides (GOS) compared to no GOS consumption increased iron absorption from an iron containing micronutrient powder by ≈60%. It is uncertain whether a lower dose of GOS can also enhance iron absorption. Another question is whether HMOs, 'natural prebiotics' found in high concentration in human breast milk, can also increase iron absorption similar to GOS. Therefore, the aim of this study is to measure fractional iron absorption from a maize-based porridge fortified with A) iron as ferrous fumarate, B) iron as ferrous fumarate and GOS and C) iron ferrous fumarate and HMOs, using an established stable iron isotope technique in 55 infants aged 8-12 months living in Msambweni and surrounding rural communities, Kwale County of southern coastal Kenya. Assessing the effect of a low dose of GOS and of HMOs on iron absorption will provide valuable information towards the development of new, highly bioavailable iron formulations for African infants. As per the local standard of care, the participants who will be iron-deficient anemic at the end of the study will be treated with oral iron supplements. To evaluate the effects of iron supplementation on iron and anemia status and to estimate obligatory iron losses in the gastrointestinal tract, blood and fecal samples will be collected before, during and fourteen days after the beginning of the treatment with oral iron supplements. Data about the efficacy of current supplementation strategies in iron-deficient anemic children and obligatory iron losses wo