The Sugar Rush

When the levels of circulating glucose begin to drop, the body signals for the reserves of glycogen to be converted back to glucose. Two small proteins, glucagon and insulin, have key roles in the regulation of this process, which works to keep the levels of glucose in the blood within a tight range around a concentration between 100 and 150 mg/dL, roughly equivalent to that of half a teaspoon of sugar dissolved in a liter of water. Within 30 minutes of consuming pure sucrose or glucose on an empty stomach, blood sugar levels rise to a peak, the so-called sugar rush. Over the next two to four hours, glucose levels will slowly fall back to their starting values, or even below, serving as one of many triggers for the complex behavior of hunger.