(SIBO) Small Intestinal Bacteria Overgrowth
Small intestinal bacterial overgrowth (SIBO) is a serious condition effecting the small intestine due to the presence of an excessive bacterial population of 105–106 organisms/mL (the normal range is less than 103 organisms/L). It develops when disruption of the homeostatic mechanisms controlling the bacteria of the small intestine occur. Causes of the overgrowth of bacteria are commonly from decreased gastric acid secretion, small intestine dysmotility where the muscles of the intestines are not working properly, improper gut immune function, anatomical abnormalities of the gut, chronic alcohol consumption, or overuse of antibiotics. When these issues trigger the overgrowth of bacteria, this causes an inflammatory response to occur in the gut which induces the symptoms of SIBO. Common symptoms of SIBO are abdominal pain or distension, bloating, diarrhea, flatulence, or feeling weak.
The type of microbial flora present, a community of bacteria that aide in intestinal function, also plays a role in the overgrowth of bacteria. An excess of microbial flora that aid in metabolizing bile salts may lead to fat malabsorption or bile acid diarrhea while an excess of bacterium that metabolize carbohydrates may lead to an increase in bloating and gas production. This is why malnutrition is a large concern for those who have SIBO due to issues with malabsorption. Fat, carbohydrate, protein, or vitamin B12 malabsorption are able to occur due to lack of proper absorption. Patients can show various symptoms ranging from being only mildly symptomatic from serious symptoms, such as chronic diarrhea, weight loss, and malabsorption. Nutritional deficiencies and osteoporosis are also common effects from SIBO. Recent research has suggested that SIBO is more prevalent than previously thought due to the increase in the advancements of diagnostic tests to diagnose SIBO. A few of the various patient populations that SIBO can occur in are those who are diabetic, have Crohn’s or Celiac disease, are malnourished or consistently taking antibiotics, have pancreatitis, and many other conditions.
In order to treat SIBO, there are three main goals. The first is correcting the underlying cause, whether it may be anatomical abnormalities, improper gut immune function, or any other cause of SIBO. This may include dietary, surgical, or medical changes. By adhering to dietary changes, this will help relieve the symptoms of SIBO significantly. For those who have been diagnosed with SIBO, an anti-inflammatory FODMAP diet is strongly recommended in order to reduce the inflammation in the gastrointestinal tract. Eating more frequent meals that are smaller in size may also be beneficial to allow for digestion to occur faster. Overeating will cause food to remain in the intestines for a longer period of time and may also effect gastric juice production. The consumption of probiotics will help get rid of the overgrowth of bacteria as well.
The second goal is to test what nutritional areas the patient is deficient in and make sure that the nutrient levels are increased so that no nutrient deficiencies are present. Vitamin B12, magnesium, and calcium are the most common areas to be deficient from SIBO. The last goal is treating the overgrowth of bacteria, which is typically done with the use of antibiotics. However, there is a high relapse rate when antibiotics are used which is why dietary changes should be the main focus in treating SIBO. With keeping these three goals in mind, the symptoms of SIBO and bacterial growth can potentially be reduced.