Blood sugar regulation cells in the pancreatic islets are among the most well understood and important. If the blood glucose level falls to dangerous levels (as during very heavy exercise or lack of food for extended periods), the alpha cells of the pancreas release glucagon, a hormone whose effects on liver cells act to increase blood glucose levels. They convert glycogen into glucose (this process is called glycogenolysis). The glucose is released into the bloodstream, increasing blood sugar. Hypoglycemia, the state of having low blood sugar, is treated by restoring the blood glucose level to normal by the ingestion or administration of dextrose
Achim Peters at an appropriate level. This goal is achieved in healthy individuals by allocating (diverting) energy from the body. The "Selfish Brain" theory represents a further development of already existing theories on the organization of the energy supply within the human organism. Blood sugar and fat deposition feedback systems constitute a complex system for regulating the intake of nutrients which is controlled by a hypothalamic center. The "Energy on demand” system for energy supply to the brain is seen as a supraordinate instance of this setup, which exerts control over the organs that regulate the blood sugar and fat feedback loops.