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"What is small intestinal bacterial overgrowth?"


I have the chronic gas and bloating that are supposed to be typical of small intestinal bacterial overgrowth, according to the internet. But what does that mean? What is SIBO, and what are its long term risks? If I go to a doctor with SIBO, how will they treat me?


Small intestinal bacterial overgrowth is a very challenging diagnosis to make, in large part because its symptoms overlap with those of many other gastrointestinal conditions. You should see your doctor to determine if, in fact, you carry this diagnosis. That being said, our small bowel normally has some bacteria in it, which help us digest our food and keep away more harmful organisms.

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Alterations in the natural bacterial balance of the small bowel, such as antibiotics or other forces, can cause a proliferation of the bacteria, and they "overgrow" the resources (food) available to them. As a result, they can allow products into the colon that prevent proper water absorption, in turn causing diarrhea. Their products can also cause excess gas and bloating (similar to lactose intolerance). With the altered bacterial flora, people can have trouble properly absorbing their nutrients, which can cause deficiencies in iron, B12, and vitamin D, among other things. These deficiencies can cause anemia (causing fatigue) and osteoporosis (predisposing you to fractures). Treatment for small intestinal bacterial overgrowth syndrome typically involves a short course of antibiotics - usually a week. This helps kill off some of the excess bacteria. Above all, it is important to return to the premise of your question, which is that you have this syndrome. Talk with your doctor about your symptoms. You will likely need further testing to determine whether you have SIBO, and discussion of specific causes and treatments can commence once the diagnosis is in hand.

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