Diabetes Mellitus, usually known simply as diabetes and sometimes "diabeetus" thanks to Wilford Brimley (R.I.P), is an
unfortunately common disorder where the pancreas gets
overworked so much that it pretty much calls it quits. The result? Your body no longer has a natural source of insulin. The most common cause is eating like you have free healthcare, which we've all been guilty of at some point.
Before the 1920s rolled around, having diabetes was a
death sentence; insulin had not been discovered yet, and the disease would ultimately take you no matter what you did. But since the discovery of insulin, people with diabetes are no longer dead men walking. But managing it is definitely no walk in the park: Insulin is not only very expensive, it's rather painful to put into your body. And you have to do it
multiple times a day. It also requires a complete change in your lifestyle (especially your diet), which some people may not take very well. Did we mention that there's 2 types of it as well?
It's commonly associated with Americans due to stereotypes (which are admittedly not far from the truth), although that's not to say it doesn't occur in other places of the world, too. A person who suffers from diabetes is called a "diabetic." Diabetes is incurable.