[7] Additionally, B. bifidum demonstrates strong adhesion to intestinal epithelial cells, a critical feature for its persistence in the gastrointestinal tract and its ability to provide health-promoting effects.

This species also plays an essential role in establishing a balanced intestinal microbiota in newborns, working alongside B. breve and B. longum subsp.

[9][10] Some people, such as those with compromised immune systems, short bowel syndrome, central venous catheters, heart valve disease and premature infants, may be at higher risk for adverse events.

[11] Rarely, consumption of probiotics may cause bacteremia, and sepsis, potentially fatal infections in children with lowered immune systems or who are already critically ill.[12] B. bifidum is among the first microbial colonizers of the infant gut, introduced through maternal transmission during birth and breastfeeding.

Its ability to persist is attributed to unique genomic features, including genes for extracellular structures like exopolysaccharides, pili, and enzymes involved in carbohydrate metabolism.

[14] These features enable B. bifidum to utilize complex dietary carbohydrates and host-derived glycans, such as mucin and human milk oligosaccharides (HMOs), providing a competitive advantage for colonization and resilience in the gut environment.

Strains capable of metabolizing HMOs and mucin demonstrate higher resilience and are better equipped for long-term colonization, making B. bifidum a crucial contributor to gut health and microbial stability across life stages.