BIFIDOBACTERIA or BIFIDOBACTERIUM are a group of good bacteria that usually live in the colon, uterus, mouth and breast milk. They are grown out of the body and purchased as probiotics. They have medicinal action in cases of diarrhea, irritable colon, common cold and flu, as well as other ailments, although there is no irrefutable scientific evidence of these benefits. They are gram-positive, not mobile, anaerobic.