What is Bifidobacterium lactis(B. lactis)? Description: Bifidobacterium lactis (B. lactis) is a multi-purpose probiotic bacteria that lives in the gut. It is a powerful strain that has been proven to fight tumor growths, improve digestion, and enhance immune system functions.  B. lactis is also responsible for breaking down body waste and aiding in the absorption of vitamins and minerals in the gut. How …