 This study examined the relationship between infant zinc levels and the composition of their gut microbiomes. Breast-fed infants had lower zinc levels than formula-fed infants, which was reflected in the lower diversity of their gut microbiomes. However, the authors did not find any correlation between zinc levels and the presence or absence of specific bacterial species. This article was authored by Maywish Durrani, Rubina Nasli, Navila Shur, and others.