(HealthDay News) -- When people with type 1 diabetes have high blood sugar (hyperglycemia), they do not have enough insulin in their system to move the sugar from the blood into the cells of the body.

Hyperglycemia also can occur in non-diabetics when a medical condition -- like an inflammation of the pancreas -- makes it difficult for the body to process sugar.

Mild hyperglycemia may have no warning signs, but symptoms tend to appear the higher a person's sugar rises.

The University of Michigan Health System lists these warning signs that your blood sugar may be getting too high:

• Blurred vision.
• Dry mouth.
• Excessive thirst.
• Increased urination.
• Fatigue.