Poster Topical Area: Nutritional Microbiology
Poster Board Number: 250
Objectives Human milk is a complex fluid, and variation in its composition is regulated by myriad factors including diet. Previous studies have indicated that variation in a mother's diet during breastfeeding can influence the microbiome of her milk (Williams et al. 2017) and feces (Carrothers et al. 2015), and even her infant's fecal microbiome (Chu et al. 2016). Here we explored associations between maternal intake of energy-yielding nutrients during breastfeeding and the infant fecal microbiome. We hypothesized that maternal lipid intake would be inversely correlated with relative abundance of infant fecal Bacteroides and positively correlated with infant fecal Escherichia and Streptococcus. Methods Maternal diet was estimated via averaging values from 24-hr diet recalls collected from 21 breastfeeding women at 9 timepoints between d 2 and 6 mo postpartum. Relative abundances of bacterial genera in infant feces were obtained via sequencing of the V1-V3 hypervariable region of the 16S rRNA gene, and also averaged across timepoints. Spearman rank correlations between dietary values and selected genera were then calculated. Results As expected, maternal lipid consumption was negatively associated with relative abundance of infant fecal Bacteroides (rs = -0.48; P = 0.03), but was not associated with relative abundances of Escherichia or Streptococcus (rs = 0.15, -0.06; P = 0.51, 0.80, respectively). However, many other associations were noted. For instance, maternal energy, carbohydrate, and lipid intakes were positively correlated with relative abundance of Akkermansia in infant feces (rs = 0.56, 0.46, 0.50; P = 0.008, 0.04, 0.02, respectively); glucose and fructose intake were inversely associated with Bifidobacterium (rs = -0.56, -0.56; P = 0.009, 0.008, respectively); and, except for cysteine, the essential amino acids were negatively associated with relative abundance of Pseudomonas (rs range: 0.47 – 0.57; P range: 0.007 – 0.03). Conclusions Chronic intakes of several energy-yielding nutrients by breastfeeding women are associated with relative abundances of various genera in their infants' fecal microbiome. We posit that these associations may be driven by alterations in the mother's gastrointestinal and/or milk microbiome, and milk nutrient content.
Funding Source: Supported by the Bill & Melinda Gates Foundation, National Science Foundation grant IOS 1344288, and NIH grant P30 GM103324.
Senior Research Scientist
University of Idaho