Type 2 diabetes mellitus (adult-onset diabetes) is a disease that interferes with the body's ability to store food, including sugar, and results in high blood sugar levels. The hormone insulin helps the body to store food and to keep blood sugar levels within the normal range. Body tissues in persons with type 2 diabetes are resistant to the effects of insulin. In addition, these patients lack effective insulin levels required to keep their blood sugar levels normal. Some patients can overcome the abnormalities by taking prescription pills, while others need to take insulin injections one or more times daily. Researchers have been exploring ways to give insulin to diabetic patients other than by injection. One alternative is inhaled insulin, whereby patients breath insulin into their lungs by using a special device.