Where to find the beneficial bacteria along your digestive tract
If you have a healthy digestive system, you have over 400 different species of micro-organisms living there. They make up 2 pounds of your body weight!
In the stomach, very few are able to survive because of the acidity. In fact, there may be as few as 10 to 100 organisms in every milliliter (.0338 fluid ounces) of stomach content.
In the small intestine there might be anywhere from 100 to 1,000 organisms per milliliter.
As you reach the junction between the small and large intestine (at the ileocecal valve), the numbers begin to grow. In the large intestine or colon, as many as 1 trillion organisms per milliliter are common.