Elsevier

The Journal of Pediatrics

Volume 163, Issue 2, August 2013, Pages 416-423.e4
The Journal of Pediatrics

Original Article
Effects of Different Complementary Feeding Regimens on Iron Status and Enteric Microbiota in Breastfed Infants

Portions of this study have been presented as abstracts at the Pediatric Academic Societies' Meeting April 30-May 5, 2011, Denver, CO and the Experimental Biology Meeting April 21-25, 2012, San Diego, CA.
https://doi.org/10.1016/j.jpeds.2013.01.024Get rights and content

Objective

To compare iron status in breastfed infants randomized to groups receiving complementary feeding regimens that provided iron from fortified infant cereals or meats, and to examine the development of the enteric microbiota in these groups.

Study design

Forty-five exclusively breastfed 5-month-old infants were randomized to 1 of 3 feeding groups (FGs)—commercially available pureed meats, iron- and zinc-fortified infant cereals, or iron-only fortified infant cereals—as the first and primary complementary food through 9-10 months of age. Dietary iron was determined by monthly 3-day diet records. Iron status was assessed at the end of the study by measurements of hemoglobin, serum ferritin, and soluble transferrin receptor levels. In a subsample of 14 infants, enteric microbiota were profiled in monthly stool samples (5-9 months) by 16S ribosomal RNA gene pyrosequencing.

Results

Infants in the 2 cereal FGs had 2- to 3-fold greater daily iron intakes versus the meat FG (P < .0001). More than one-quarter (27%) of the infants had a low serum ferritin level, and 36% were mildly anemic, with no significant differences by FG; more infants in the meat FG had a high soluble transferrin receptor value (P = .03). Sequence analysis identified differences by time and FG in the abundances of several bacterial groups, including significantly more abundant butyrate-producing Clostridium group XIVa in the meat FG (P = .01)

Conclusion

A high percentage of healthy infants who were breastfed-only were iron-deficient, and complementary feeding, including iron exposure, influenced the development of the enteric microbiota. If these findings are confirmed, then reconsideration of strategies to both meet infants' iron requirements and optimize the developing microbiome may be warranted.

Section snippets

Methods

The iron status and microbiome outcomes were secondary outcomes in a previously reported randomized controlled intervention trial investigating zinc absorption from different complementary feeding regimens.11 In brief, healthy term infants were assigned at random to 1 of 3 feeding groups (FGs): commercially available pureed meats; iron- and zinc-fortified infant cereals; or organic, whole grain iron-only fortified infant cereals. These foods served as the first complementary food and as a

Results

Monthly diet records indicated iron intakes reflective of the assigned feeding regimens. At every month, mean iron intake in the iron- and zinc-fortified cereal and iron-fortified cereal FGs did not differ and significantly exceeded that of the meat FG (Figure 2). At 9 months, the average number of daily servings of the assigned intervention food did not differ among the FGs (1.6 for the iron- and zinc-fortified cereal FG, 1.3 for the iron-fortified cereal FG, and 2 for the meat FG). Likewise,

Discussion

Available systematic comparisons of the effects of different complementary feeding patterns on nutritional outcomes in breastfed infants are very limited. Several important findings emerge from the present study. First, iron deficiency and iron-deficiency anemia were surprisingly common in this cohort of healthy breastfed infants, regardless of FG. Second, the lack of correlation between dietary iron intake and biomarkers of iron status emphasizes the importance of other factors, including

References (42)

  • Pediatric nutrition handbook

    (2009)

  • Recommendations for preventing and controlling iron deficiency in the United States

    Morb Mortal Recomm Rep

    (1998)

  • Guiding principles for complementary feeding of the breastfed child

    (2003)
  • K.M. Hambidge et al.

    Evaluation of meat as a first complementary food for breastfed infants: impact on iron intake

    Nutr Rev

    (2011)
  • R. Hurrell et al.

    Iron bioavailability and dietary reference values

    Am J Clin Nutr

    (2010)
  • A.M. Siega-Riz et al.

    Food consumption patterns of infants and toddlers: where are we now?

    J Am Diet Assoc

    (2010)
  • D.L. Dee et al.

    Sources of supplemental iron among breastfed infants during the first year of life

    Pediatrics

    (2008)

  • Dietary reference intakes for vitamin A, vitamin K, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc

    (2001)
  • M.B. Zimmermann et al.

    The effects of iron fortification on the gut microbiota in African children: a randomized controlled trial in Cote d'Ivoire

    Am J Clin Nutr

    (2010)
  • C. Palmer et al.

    Development of the human infant intestinal microbiota

    PLoS Biol

    (2007)
  • N.F. Krebs et al.

    Comparison of complementary feeding strategies to meet zinc requirements of older breastfed infants

    Am J Clin Nutr

    (2012)
  • J.A. Frank et al.

    Critical evaluation of two primers commonly used for amplification of bacterial 16S rRNA genes

    Appl Environ Microbiol

    (2008)
  • D.J. Lane

    16S/23S rRNA sequencing

  • D.N. Frank

    BARCRAWL and BARTAB: software tools for the design and implementation of barcoded primers for highly multiplexed DNA sequencing

    BMC Bioinformatics

    (2009)
  • E. Li et al.

    Inflammatory bowel diseases phenotype, C difficile and NOD2 genotype are associated with shifts in human ileum associated microbial composition

    PLoS ONE

    (2012)
  • D.N. Frank et al.

    The human nasal microbiota and Staphylococcus aureus carriage

    PLoS ONE

    (2010)
  • E.P. Nawrocki et al.

    Infernal 1.0: inference of RNA alignments

    Bioinformatics

    (2009)
  • J.J. Cannone et al.

    The comparative RNA web (CRW) site: an online database of comparative sequence and structure information for ribosomal, intron, and other RNAs

    BMC Bioinformatics

    (2002)
  • R.R. Gutell et al.

    The accuracy of ribosomal RNA comparative structure models

    Curr Opin Struct Biol

    (2002)
  • B.J. Haas et al.

    Chimeric 16S rRNA sequence formation and detection in Sanger and 454-pyrosequenced PCR amplicons

    Genome Res

    (2011)
  • Q. Wang et al.

    Naive Bayesian classifier for rapid assignment of rRNA sequences into the new bacterial taxonomy

    Appl Environ Microbiol

    (2007)

    • Cited by (0)

    Supported by the National Institutes of Health (NIH; T32DK007658-20S, K24DK083772, and HG005964), NIH/National Center for Research Resources (UL1TR000154 to Colorado Clinical and Translational Sciences Institute), and National Cattlemen's Beef Association (Beef Checkoff). The authors declare no conflicts of interest.

    View full text
    Copyright © 2013 Mosby, Inc. All rights reserved.