80 is healthy at any time. Recommended maximums are: Fasting blood sugarunder 100 mg/dl (5.5 mmol/L)One hour after mealsunder 140 mg/dl (7.8 mmol/L)Two hours after mealsunder 120 mg/dl (6.6 mmol/L) See also the attached link for more information. 80 is healthy at any time.