The diaphragm must drop downward into the belly area when you breathe in. If the stomach, liver, colon etc is too large the diaphragm can not lower to take your easiest deepest breath.
This lack of downward movement allows toxins to slowly build up an collect in the large intestine (colon).
Key signs that has happened are constipation (click on picture) and a pot gut.
Poor digestion is the primary contributor to constipation. More than 2 minutes on the pot means you took too long and forced too much.