What is small intestinal bacterial overgrowth (SIBO)? Small intestinal bacterial overgrowth (SIBO) is an overgrowth of nonpathogenic bacteria in the small intestine [2]. Normally, there is only a small amount of bacteria in the small intestine (they are mostly in the large intestine), but they may overgrow under certain conditions. The main symptom is abdominal […] The post Small Intestinal Bacterial Overgrowth (SIBO) appeared first on Nutrients Review.