A normal blood sugar level after eating depends on the age of the person, according to WebMD. For a person who is 50 years old and younger, blood sugar levels in the normal range are 140 milligrams per deciliter or less.
For someone who is between 50 and 60 years old, normal postprandial blood sugar levels are less than 150 milligrams per deciliter, and for people over 60, the normal level is less than 160 milligrams per deciliter, notes WebMD.
A blood test to check blood sugar levels is performed two hours after eating, notes the University of Rochester Medical Center. The test is done to ensure proper insulin levels in patients who have diabetes.