Diabetes mellitus interferes with the body's ability to store energy from food. The pancreas makes insulin, a substance that helps to store energy from food. Type 1 diabetes mellitus (also called juvenile diabetes) occurs when the pancreas stops making insulin. In type 2 diabetes mellitus (also called adult-onset diabetes), the body makes plenty of insulin but cannot use it normally. In both types, the result is high blood sugar levels. Over time, high blood sugar levels can lead to blindness, kidney failure, nerve damage, and heart disease. Fortunately, good care with diet, exercise, and medications to keep blood sugar levels under control can prevent the development of complications. The control of blood pressure and cholesterol levels is also very important for patients with diabetes. Because these can be accomplished with good care, it is important to know about the general quality of diabetes care in the United States. In 2002, researchers reported on the quality of diabetes care in the United States for the years 1988 to 1995. At that time, they noted that it would be valuable to check the general quality of diabetes care in the United States every few years to see whether care was improving.