Islets are the cells that produce insulin within the pancreas.

With juvenile diabetes mellitus, the islets are destroyed so no insulin is produced; thus, you have the necessity of artificial insulin to replace what the body should have made. It is so difficult to balance eating and exercising the exact amount each day to the same amount of insulin that you inject. Diabetes, insulin-dependent, is a balancing act that goes on 24 hours a day. It can be done, though, and many people do it very well. Don't give up hope. Keep at it day in and day out!!!