Effect of breast milk with or without bacteria on infant gut microbiotaOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
Whether the presence of bacteria in breast milk shapes the infant gut microbiota, comparing infants fed bacteria-containing milk versus sterile milk.
How was it studied?
Seventeen healthy pregnant women and their 17 infants were enrolled. Maternal fecal samples were collected at term, and milk plus infant fecal samples were collected on postnatal day 14. All samples underwent 16S rRNA sequencing, and mother-infant pairs were grouped by whether milk bacteria were detectable.
What did they find?
Bacteria were detected in 11 of 17 milk samples, a 64.7 percent detection rate. Infants fed bacterial milk had higher Shannon and Simpson diversity indices (P = 0.020, P = 0.048) and markedly higher relative abundance of Lachnospirales, Lachnospiraceae and Eggerthellaceae. Their gut microbiota also showed more bacterial co-occurrence network associations. Mothers with sterile versus bacterial milk did not differ in clinical characteristics or milk microbial composition and diversity.
Why it matters
The findings suggest live bacteria in breast milk, when present, may help build a more diverse and interconnected infant gut microbiome. The reason some milk yields no detectable bacteria remains unexplained and needs further research.