Simply put, Small Intestine Bacterial Overgrowth is a chronic bacterial infection of the small intestine.  The infection is of bacteria that normally live in the gastrointestinal tract but have abnormally overgrown in a location not meant for so many bacteria.  

The Problem
The bacteria interfere with our normal digestion and absorption of food and are associated with damage to the lining or membrane of the SI (leaky gut syndrome, which I prefer to call leaky SI in this case). 

• They consume some of our food which over time leads to deficiencies in their favorite nutrients such as iron and B12, causing anemia.

• They consume food unable to be absorbed due to SI lining damage, which creates more bacterial overgrowth (a vicious cycle).

• After eating our food, they produce gas/ expel flatus, within our SI.  The gas causes abdominal bloating, abdominal pain, constipation, diarrhea or both (the symptoms of IBS).  Excess gas can also cause belching and flatulence.

• They decrease proper fat absorption by deconjugating bile leading to deficiencies of vitamins A & D and fatty stools.

• Through the damaged lining, larger food particles not able to be fully digested, enter into the body which the immune system reacts to.  This causes food allergies/ sensitivities.

• Bacteria themselves can also enter the body/bloodstream.  Immune system reaction to bacteria and their cell walls (endotoxin) causes chronic fatigue and body pain and burdens the liver.

• Finally, the bacteria excrete acids which in high amounts can cause neurological and cognitive symptoms.