Numbers of intestinal bifidobacteria decrease with age, especially Bifidobacterium bifidum and Bifidobacterium breve, while Bifidobacterium adolescentis might be increasing, in the continuous process of transformation of microbiota.
Some bifidobacteria are used as probiotics to prevent or treat diarrhea and particular bowel infections Bifidobacterium also have anti-tumor qualities. Manipulating the microbiota may modulate cancer immunotherapy.