Bifidobacterium adolescentis is a probiotic species that has been investigated for its potential role in supporting inflammatory bowel diseases, including Crohn's Disease (CD). The rationale for its use stems from scientific studies that suggest alterations in gut microbiota composition (dysbiosis) are associated with Crohn's Disease, and that restoring balance may have therapeutic benefits.

Several small clinical studies and preclinical (animal and in vitro) research have explored the effects of B. adolescentis and related bifidobacterial species in IBD. Some studies have found that B. adolescentis can enhance the intestinal epithelial barrier, modulate immune responses (e.g., by increasing anti-inflammatory cytokines like IL-10 and reducing pro-inflammatory cytokines like TNF-alpha), and suppress pathogenic bacteria. However, direct evidence from large, high-quality randomized controlled trials specifically demonstrating efficacy in Crohn's Disease patients is limited.

Reviews of probiotics in IBD often mention Bifidobacterium species as promising, but most strong evidence relates to ulcerative colitis or pouchitis, not Crohn's Disease per se. The overall evidence for B. adolescentis in Crohn's Disease is still considered preliminary, with more robust clinical trials needed. Thus, while there is a scientific rationale and some early-stage evidence, the strength and direct applicability of this evidence are modest.