Postprandial Glucose

Postprandial glucose is the concentration of glucose in the blood during the period after eating a meal. It reflects the balance between glucose entering the circulation, endogenous glucose production, and glucose uptake by the liver and other tissues. The term can refer to a glucose measurement taken at a specified time after a meal or more broadly to the pattern of glucose concentrations during the post-meal period .¹

As digestible carbohydrate is broken down, glucose is absorbed from the small intestine and enters the portal circulation. This tends to raise blood glucose, while coordinated physiological responses limit the rise. Insulin secretion increases, promoting glucose uptake and storage and suppressing endogenous glucose production. Incretin hormones released from the intestine help regulate insulin and glucagon secretion, while the liver and peripheral tissues, particularly skeletal muscle, contribute to glucose uptake and metabolism .¹

The magnitude and timing of the postprandial glucose response depend on several interacting factors. These include the amount and form of carbohydrate consumed, gastric emptying, intestinal glucose absorption, secretion and action of insulin and glucagon, incretin responses, and the ability of tissues to take up glucose. Gastric emptying is particularly important because it helps determine how rapidly carbohydrate reaches the small intestine for digestion and absorption .^1,2

Postprandial glucose is distinct from fasting glucose, which is measured after a period without caloric intake and reflects glucose regulation in the fasting state. It is also distinct from the postprandial glucose excursion, which describes the change in glucose from the pre-meal level rather than the post-meal concentration itself .¹