You are talking about an intusception. I may have spelled that wrong.
It's where the bowel loops in on itself, as it moves.
I had what is called an Ileus
, that is related to the intussception.
http://www.merckmanuals.com/professional/gastrointestinal_di sorders/acute_abdomen_and_surgical_gastroenterology/ileus.ht ml
Basically, our bowels have been reconstructed (not entirely - just portions).
When they become much more (or much less
) active as we adapt to our changed intake and activity, they move differently. Not just in the sense of expediting the material THROUGH them ,but also move differently within our bellies. They can move a lot less or a lot more than before, and all those loops can twist around themselves. Just like when you have a bunch of necklaces in a drawer and they all get tangled.
Do a search on Bowel Obstruction on ObesityHelp's main page - you will find more information on there.
And "rotting' is probably not the way to describe the process when the tissue gets cut off from its blood supply and necrotizes. That's a very graphic word, and probably more fear-instilling than anything else.