Few recent studies show that birthing parents with inflammatory bowel disease had low abundance of Bifidobacterium and lower abundance of proteins involved in immune regulation, including thymic stromal lymphopoietin, IL-12 subunit beta, tumor necrosis factor (TNF)-beta, and C-C motif chemokine 20 in their human milk compared to birthing parents without inflammatory bowel disease (Sabino et al., 2023). This evidence concerns the gene TSLP and inflammatory bowel disease.