8. Dehydration
It is hard to explain why this method, number 8 on our list of most painful worst ways to die is painful. The medical explanation starts from the smaller parts of the human body, cells. If they are empty, they are looking for the energy and the source of the oxygen, usually got from the water. During that period, they are shrinking, saving the last reserves of the oxygen, which causes pain. After a while, organs start with shrinking, and in the end they need to shut down.