Small Intestinal Bacterial Overgrowth

SIBO is a cause of malabsorption of food in the small intestine. The small intestine does not have a high number of bacteria unlike the large intestine.  When there are too many bacteria in the small intestine the bacteria uses up the nutrients (carbohydrates) that would otherwise be used by the body for fuel.  It can also damage the intestinal lining.

There are a variety of conditions that can lead to SIBO:

  • Crohn’s Disease
  • AIDS/Immunoglobulin deficiency
  • Diabetes
  • Scleroderma
  • Short bowel syndrome
  • Surgical procedure that create a loop of small intestine
  • IBS


  • Abdominal fullness
  • Abdominal pain/cramps
  • Diarrhea
  • Gassiness
  • Fatty stool
  • Weight loss


SIBO – Specific Carbohydrate diet (SCD), Gut and Psychology Syndrome diet (GAPS) , Low Fodmap diet (LFD), and a consistent regime of antibiotics to help decrease the bacteria in the small intestine.

References:  Semrad CE. Approach to the patient with diarrhea and malabsorption. In:  Goldman L, Schafer Al, eds. Goldman’s Cecil Medicine. 24th ed Philadelphia, PA


Lisa Edwards, MOTR/L, BSRS