Bacteria and other infections survive and thrive in a structure that bacteria create around themselves called biofilm, a sticky film made to ensure their survival. Biofilm didn't exist in significant quantities in the human body until the invention of antibiotics but now plagues almost everyone. You can see biofilm outside the body around the drains of sinks. It's that gooey orange film that soap and most solvents don't wash away and that keeps returning between cleanings. It's present throughout the digestive tract and leads to all sorts of digestive conditions like GERD, skin conditions like fibromyalgia, fungal infections like candida and serious diseases by harboring infections and allowing them to grow, protected under the layer of goo.
Biofilm needs to be stripped from the intestinal tract so the intestines can work properly.
Here's some more background information:
http://bodyecology.com/articles/biofilm-how-this-slimy-coating-is-causing-chronic-fatigue-fibromyalgia-irritable-bowel-and-more 
