It is normal for blood sugar levels to rise immediately after a meal. The increased glucose is a product of the carbohydrates in the food that was just consumed. The higher blood glucose triggers the pancreas to produce more insulin. This release of insulin usually takes place within about 10 minutes of eating. The insulin removes the glucose from the blood and stores it for the body to use as energy. In a healthy individual, blood glucose levels should return to a normal level within about two hours after finishing the meal. In diabetics, the blood sugar level often remain elevated for a longer period because of the body’s inability to produce or utilize insulin properly.An elevated two-hour postprandial (after a meal) blood sugar may indicate diabetes or prediabetes. As a general rule, a normal two- hour postprandial blood sugar is as follows:

• Age 50 and under: Less than 140 mg/dl
• Age 50 – 60: Less than 150 mg/dl
• Over age 60: Less than 160 mg/dl

A doctor may recommend different postprandial blood sugar levels based on an individual’s particular circumstances and health history.

Several factors may cause a person’s postprandial blood sugar to remain elevated.

• Smoking after the meal: Studies show that smoking raises blood sugar levels in people with diabetes.
• Extreme stress: Stress produces the body’s fight-or-flight response triggering the release of stress hormones such as cortisol. These hormones cause the body to release the glucose it has previously stored for energy.
• Eating or drinking after the meal and before testing the blood sugar: Continuing to eat will keep blood sugars closer to their immediate post-meal levels.

Studies show that 15 to 20 minutes of moderate exercise, such as walking, shortly after a meal may improve glucose metabolism and reduce postprandial glucose levels.