Bifidobacteria are one variety of “good” bacteria that live in a healthy intestinal tract. Since bifidobacteria exist naturally in your gastrointestinal system, you might guess that nature intends bifidobactera to serve a specific purpose there, and your guess would be correct. Along with many of the other gut flora, which is the collective term for the bacteria that occur naturally in your intestines, bifidobacteria aid in the food digestion process.