Healthy blood sugar levels are 100 milligrams per deciliter 8 hours after eating and 140 mg/dL 2 hours after eating, as detailed by WebMD. Blood sugar levels are typically at their lowest before meals, when they may be as low as 60 mg/dL, but are usually between 70 and 80 mg/dL.
Generally, the liver maintains a blood sugar level of 60 mg/dL or above by turning fat or muscle tissue into sugars, even after extended periods of fasting.
If the blood sugar level is higher than 126 mg/dL 8 hours after eating, it may be indicative of diabetes, according to WebMD. Diabetes may also be diagnosed if, after consuming a sugary drink at the end of these 8 hours, the blood sugar level elevates to beyond 200 mg/dL after a period of 2 hours.