Diabetes (both Type 1 and 2) is a disease that affects every part of the body in many different ways. Your feet are no exception.
Due to the high blood sugar that comes with diabetes, the risk of several negative changes happening in your feet increases. Blood vessels feet can become clogged with plaque or harden. This will decrease blood flow or circulation to your feet. Because your feet aren't getting the blood flow that they need, any cut or break in the skin puts you at higher risk for infection, wounds that take longer to heel, and worst case scenario amputation.
Another phenomenon seen in diabetic feet is something known as peripheral neuropathy. Also due to the high blood sugar with diabetes, nerves in the feet become damaged. This can lead to numbness in the feet, burning, tingling, or pain. If someone cannot feel their feet, they also cannot know if they have been injured just by feeling pain alone. This can lead to possibly life-threatening infections and or amputation, due to the delayed treatment of the wound.