Food adds weight. The more pounds you put on, the higher your blood sugar goes up. High blood sugar leads to medical complications. Often neuropathy sets in, meaning that you get numbness in your feet and other areas. If you're not wearing shoes, you can step on something sharp and not feel it.
Infection sets in.
As a result, diabetics often lose their toes or feet. It is a disease that will kill you one limb at a time if you let it. The list of health complications resulting from mismanagement of diabetes also includes loss of eyesight and heart attacks. And it all starts with food. Of course not.