The ideal blood glucose range for men younger than 50 is 50 to 100 milligrams per deciliter after fasting for 8 hours, according to WebMD. Blood glucose levels of up to 140 milligrams per deciliter are acceptable 2 hours after eating.
Typically, blood glucose levels for healthy adults range from 80 to 120 milligrams per deciliter before eating in the morning to 100 to 140 milligrams per deciliter in the evening, notes WebMD. High values of glucose in the blood can be caused by medical conditions, such as diabetes and Cushing's syndrome, and by some medications. Values lower than normal may indicate excessive insulin, liver or kidney problems, hypothyroidism, or malnutrition.