In response to high levels of glucose in the blood, the insulin-producing cells in the pancreas secrete the hormone insulin. Type I diabetes occurs when these cells are destroyed by the body’s own immune system.
Review Date: 6/18/2013 Reviewed By: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.