It's a metabolic disease in which the body’s inability to produce any or enough insulin causes elevated levels of glucose in the blood. Or that's the dictionary definition anyway.

In much more simpler terms, if you eat too much sugar your body stops being able to process the things it needs to handle it. Best case scenario you need a shot to help your body out. Worst case... you die.

[He shrugs and continues to much on his treat. Most worst case medical scenarios end with death. But he's just here to tell it like it is. Bedside manner is not where he excels.]