Blood sugar regulation

Blood sugar regulation refers to the process by which the levels of blood sugar, primarily glucose, are maintained by the body within a narrow range. This tight regulation is referred to as glucose homeostasis. Insulin, which lowers blood sugar, and glucagon, which raises it, are the most well known of the hormones involved, but more recent research has also implicated other hormones, including cortisol and the growth hormone.

Mechanisms of Blood Sugar Regulation

The primary mechanisms of blood sugar regulation occur in the pancreas, which produces the hormones insulin and glucagon.

Insulin

Insulin is produced by the beta cells of the pancreas in response to high levels of blood glucose, such as in the period following a meal. Insulin facilitates the uptake of glucose into cells, either for immediate use as energy or to be stored as glycogen or fat. This has the effect of lowering blood glucose levels.

Glucagon

In contrast, glucagon is produced by the alpha cells of the pancreas when blood glucose levels are low. Glucagon promotes the breakdown of glycogen to glucose in the liver, which is then released into the blood, thereby raising blood glucose levels.

Other Hormones Involved in Blood Sugar Regulation

Other hormones also play a role in blood sugar regulation. These include:

• Cortisol: This hormone increases blood sugar levels by promoting gluconeogenesis, the production of glucose from non-carbohydrate sources.
• Growth hormone: This hormone also raises blood sugar levels by reducing the uptake of glucose by cells and promoting the breakdown of fat for energy.

Disorders of Blood Sugar Regulation

Disorders of blood sugar regulation can lead to either hypoglycemia, abnormally low blood sugar levels, or hyperglycemia, abnormally high blood sugar levels. Chronic hyperglycemia is a defining characteristic of diabetes mellitus, a disease characterized by insufficient insulin production or resistance to the effects of insulin.

See Also

• Diabetes mellitus
• Hypoglycemia
• Hyperglycemia
• Insulin
• Glucagon
• Cortisol
• Growth hormone