Based on previous data generated in our laboratory (and others), we propose that repeated episodes of hypoglycemia are associated with a deterioration in the "body sensor" for hypoglycemia in diabetes. Moreover, since many studies have shown that such deterioration in the response to hypoglycemia can be induced also by exercise (patients with diabetes are at greater risk for hypoglycemia after exercise), we propose that exercise (and other stresses) affect the hypoglycemia response by endorphin release (endorphins are proteins responsible for inhibition of the neuroendocrine response system).