There are many reasons that affect flora imbalance, which are mainly divided into internal and external factors: internal factors: anatomical structure, physiological function and immune state can all cause flora imbalance. For example:
(1) When the gastric acid decreases, the bacteria in the stomach increase, and the aerobic and anaerobic bacteria in the small intestine increase, so harmful bacteria may take advantage of it and become active.
(2) When intestinal peristalsis slows down, the number of bacteria in small intestine increases, which is easy to form bacterial overgrowth syndrome;
(3) When bile secretion decreases, bacteria in small intestine also increase;
(4) Mucus on mesentery is reduced, and flora loses moisture and regulates environment;
(5) Anatomical changes, such as the destruction of normal flora after gastrointestinal surgery;
(6) The immunity of human body decreases, and the phagocytic ability of harmful bacteria invading from outside is lost or reduced, and the protective ability is reduced;
(7) The structure and quantity of flora will be disrupted after human illness, whether acute or chronic.