INS and Hyperglycemia: A recent study investigating the metabolic effects of sleep deprivation and circadian disruption in adult human volunteers found relative hyperglycemia after the breakfast meal in sleep deprived subjects because of inadequate glucose-triggered insulin secretion, hypothesized to be due to desynchronization between the central circadian pacemaker and the response of circadian oscillators in peripheral tissues to sleep-wake and fasting-feeding cycles [28].