As they travel through the bowel, the action of gut bacteria causes gas production, bloating, pain and altered bowel patterns in some people. (latashaskitchen.com)
SIBO in particular can be the root cause of IBS and other mental health complaints which can include abdominal pain, bloating, gas, nausea, change in bowel pattern as well as fatigue, brain fog, anxiety and even depression. (parsleyhealth.com)