In this episode, Dennis M. Bier MD Young Career Editor Kevin C. Klatt, PhD, RD speaks with a distinguished team of authors about their recent work published in the American Journal of Clinical Nutrition titled “Metagenomic profile of the fecal microbiome of preterm infants consuming mother's own milk with bovine milk-based fortifier or infant formula: a cross-sectional study”. In this episode, we dive into the rationale for this newest work examining the relationship between the mode of feeding for preterm infants and the metagenomic potential of their microbiome, as well as discussing emerging methods for characterizing the microbiome composition and function and the challenges of identifying how environmental factors influence this. Be sure to connect with us! AJCN: @AJCNutrition; Dr. Klatt: @kcklatt. Find all of the publications from the American Society for Nutrition (@nutritionorg; @jnutritionorg) at our website: https://nutrition.org/publications/.