Cause

Complications from type 1 diabetes are caused by one or both of the following:

• Damage to the lining of the blood vessels throughout your body, causing them to become clogged with hard, fatty deposits called plaques. This process is called atherosclerosis.
• Damage to the nerves (neuropathy) that reduces or blocks their ability to send messages to your organs, legs and arms, and other parts of your body.

This damage results from excess sugar (glucose) in your body.