Consumption of galacto-oligosaccharides increases iron absorption from a micronutrient powder containing ferrous fumarate and sodium iron EDTA: a stable-isotope study in Kenyan infants [Vitamins, minerals, and phytochemicals]
- © 2017 American Society for Nutrition
- Daniela Paganini1,
- Mary A Uyoga3,
- Colin I Cercamondi1,
- Diego Moretti1,
- Edith Mwasi4,
- Clarissa Schwab2,
- Salome Bechtler1,
- Francis M Mutuku5,
- Valeria Galetti1,
- Christophe Lacroix2,
- Simon Karanja3, and
- Michael B Zimmermann1
1Laboratories of Human Nutrition and
2Food Biotechnology, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland;
3College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya;
4Department of Pediatrics, Msambweni County Referral Hospital, Msambweni, Kenya; and
5Technical University of Mombasa, Mombasa, Kenya
- Address correspondence to MBZ (e-mail: ).
Background: Whether consumption of prebiotics increases iron absorption in infants is unclear.
Objective: We set out to determine whether prebiotic consumption affects iron absorption from a micronutrient powder (MNP) containing
a mixture of ferrous fumarate and sodium iron EDTA (FeFum+NaFeEDTA) in Kenyan infants.
Design: Infants (n = 50; aged 6–14 mo) consumed maize porridge that was fortified with an MNP containing FeFum+NaFeEDTA and 7.5 g galacto-oligosaccharides
(GOSs) (Fe+GOS group, n = 22) or the same MNP without GOSs (Fe group, n = 28) each day for 3 wk. Then, on 2 consecutive days, we fed all infants isotopically labeled maize porridge and MNP test
meals containing 5 mg Fe as 57FeFum+Na58FeEDTA or ferrous sulfate (54FeSO4). Iron absorption was measured as the erythrocyte incorporation of stable isotopes. Iron markers, fecal pH, and bacterial
groups were assessed at baseline and 3 wk. Comparisons within and between groups were done with the use of mixed-effects models.
Results: There was a significant group-by-compound interaction on iron absorption (P = 0.011). The median percentages of fractional iron absorption from FeFum+NaFeEDTA and from FeSO4 in the Fe group were 11.6% (IQR: 6.9–19.9%) and 20.3% (IQR: 14.2–25.7%), respectively, (P < 0.001) and, in the Fe+GOS group, were 18.8% (IQR: 8.3–37.5%) and 25.5% (IQR: 15.1–37.8%), respectively (P = 0.124). Between groups, iron absorption was greater from the FeFum+NaFeEDTA (P = 0.047) in the Fe+GOS group but not from the FeSO4 (P = 0.653). The relative iron bioavailability from FeFum+NaFeEDTA compared with FeSO4 was higher in the Fe+GOS group than in the Fe group (88% compared with 63%; P = 0.006). There was a significant time-by-group interaction on Bifidobacterium spp. (P = 0.008) and Lactobacillus/Pediococcus/Leuconostoc spp. (P = 0.018); Lactobacillus/Pediococcus/Leuconostoc spp. decreased in the Fe group (P = 0.013), and there was a nonsignificant trend toward higher Bifidobacterium spp. in the Fe+GOS group (P = 0.099). At 3 wk, iron absorption was negatively correlated with fecal pH (P < 0.001) and positively correlated with Lactobacillus/Pediococcus/Leuconostoc spp. (P = 0.001).
Conclusion: GOS consumption by infants increased iron absorption by 62% from an MNP containing FeFum+NaFeEDTA, thereby possibly reflecting
greater colonic iron absorption. This trial was registered at clinicaltrials.gov as NCT02666417.
Abbreviations used: AGP, α-1-acid glycoprotein; CRP, C-reactive protein; FTU, phytase unit; GOS, galacto-oligosaccharide;
MNP, micronutrient powder; NaFeEDTA, sodium iron EDTA; PF, plasma ferritin; qPCR, quantitative polymerase chain reaction;
SCFA, short-chain fatty acid; sTfR, soluble transferrin receptor.
- Received September 8, 2016.
- Accepted July 6, 2017.