How does small intestinal bacterial overgrowth cause symptoms?
When bacteria digest food in the intestine, they produce gas. The gas can accumulate in the abdomen giving rise to abdominal bloating or distension. Distension can cause abdominal pain. The increased amounts of gas are passed as flatus (flatulence or farts). The bacteria also probably convert food into substances that are irritating or toxic to the cells of the inner lining of the small intestine and colon. These irritating substances produce diarrhea (by causing secretion of water into the intestine). There is some evidence that the production of one gas by the bacteria-methane-causes constipation. Bacteria in the small intestine, when present in large numbers, can compete with the human host for the food that is eaten. This can lead to malnutrition with vitamin and mineral deficiencies. In advanced cases of SIBO, the bacteria use up enough food that there are insufficient calories for the host, thereby leading to weight loss. How is small intestinal bacterial overgrowth diagnosed? Cu
