The ideal blood glucose level changes for children and adults, and varies depending on situation, too: for a diabetes diagnosis in fasting adults, blood glucose levels exceed 200 mg/dL, while preteens and teens classify as diabetic with blood glucose levels of 180 mg/dL and 150 mg/dL, respectively. Patients with diabetes experience fluctuating blood glucose levels from several factors, including level of stress, use of some medications and even age. Upon reaching puberty, adolescents' hormones change, too, which experts at WebMD say impacts blood sugar levels.
Blood glucose levels change throughout the day for children and adults, and may fluctuate within the normal range without causing problems. Some people may even have blood sugar levels slightly above or below the recommended level without experiencing problems. However, experts use a chart to give diabetics numbers to strive for. Children between the ages of 6 and 12 should strive for maximal blood glucose levels below 180 mg/dL after fasting, before a meal and at night, say experts at WebMD. For teenagers, having blood sugar levels below 150 mg/dL after fasting and at night is ideal. For both groups, having blood sugar levels of 150 mg/dL before exercising is ideal. For adults, fasting blood sugar levels between 70 and 99 mg/dL is ideal and 2 hours after a meal, that number should fall below 140 mg/dL.