Intestinal bacteria can cause acidic environment intestinal, conducive to the growth of their own, at the same time control the growth of harmful bacteria, keep beneficial intestinal health. In normal human body beneficial and harmful bacteria can balance, once out of balance, the disease will be waiting in the wings. In the cold, diarrhea, constipation, peptic ulcer, cirrhosis patients, the phenomenon that the intestinal bacteria reduced and harmful bacteria is relatively increased can be found.