When I first encountered this statement, I found it to be rather mysterious. It took me years of experimentation to understand it's meaning. It starts in the mouth, then the stomach, duodenum, small intestine, and finally the large intestine, also called the colon. Each stage has a special job to do. If digestion in stages one through four are inadequate, then a mess is dumped into the colon .
Undigested food can stick to the sides of the colon.
It can imbed itself into the colon walls, stay there for years, and attract parasites, yeast, bacteria, and viruses. The walls of the colon can become diseased , and allow stuff to get into the bloodstream that doesn't belong there. The liver can remove some of this, but only up to a point. We will be examining this whole process very carefully, and there are a number of things that we can do to help the body along. Digestion takes place with enzymes .