Your blood sugar level after a meal, or postprandial blood glucose, reflects how your body responds to an influx of glucose from food. Abnormally high or low blood sugar levels after meals may indicate diabetes. Whether or not you've been diagnosed with diabetes, consistently high after-meal blood glucose puts you at risk for heart disease and heart attack. For any diagnosis, you'll need laboratory blood tests because home fingerstick devises aren't as accurate.
Normal Postprandial Blood Sugar
A normal blood sugar level two hours after the start of a meal ranges from 70 to 145 mg/dL, or 3.9 to 8.1 mmol/L, explains Registered Dietitian Christine Wendt in an article for Healthwise. This normal range is the same for adults and children. Ideally, your blood sugar shouldn't be over 120 mg/dL, or 6.7 mmol/l, two hours after a meal. If you have diabetes, however, your postprandial blood sugar may rise as high as 180 mg/dL, or 10.0 mmol/l, and still be within a typical range. Your health care provider can help you determine the range that's healthy for you.
High Postprandial Blood Sugar
Blood glucose levels that are higher than normal, or over 70 to 145 mg/dL, or 3.9 to 8.1 mmol/L, after meals may indicate pre-diabetes or diabetes. An after-meal blood glucose level above 180 mg/dL, or 10.0 mmol/l, constitutes postprandial, or reactive, hyperglycemia. If you find your blood sugar levels after meals are consistently above 160 to 180 mg/dL, or 8.9 to 10 mmol/l, consult your health care provider. If you have diabetes, your target postprandial blood glucose level may be as high as 200 mg/dL, or 11.1 mmol/L, but because this is unusually high, a health care professional should help you determine whether or not this level is healthy for you. Even if you don't have diabetes, illness and infections can temporarily raise your blood sugar, as can kidney disease, liver disease and pancreatic infections.
Low Postprandial Blood Sugar
For those not taking hypoglycemic medications, a blood glucose level lower than 70 mg/dL, or 3.4 10 mmol/l, within 2 to 5 hours after starting a meal constitutes symptomatic, or reactive, hypoglycemia. Experts disagree on the causes and implications of this condition, note Drs. Ari Eckman and Christopher Saudek in the Diabetes Guide of Trinidad and Tobago. In theory, elevated after-meal blood sugar may be due to the pancreas releasing insulin in a delayed but excessive manner, which may indicate pre-diabetes. Symptoms of reactive hypoglycemia may include sweating, trembling, heart palpitations, anxiety and hunger.
Managing Your Blood Sugar
The glycemic index ranks how fast and how high a particular food can raise our blood glucose. If you have diabetes, but your pre-meal blood glucose levels are normal, you may be able to avoid high post-meal blood glucose levels by eating low-glycemic-index foods like vegetables and meats rather than high-glycemic-index foods like pasta and fruits. Light exercise, such as walking, after your meal may also help control your postprandial blood sugar, explains Certified Diabetes Educator Gary Scheiner at the website Mendosa.com. If your after-meal blood sugar levels remain high, however, consult your health care provider. To reduce your risk of postprandial hypoglycemia, try eating small meals or snacks approximately every three hours. Include high-fiber foods and protein in each meal and limit simple sugars like candy, as well as alcohol and caffeine.
References
- Healthwise; Blood Glucose; Christine Wendt; July 14, 2009
- University of Cincinnati; Normal Blood Sugar?; Nancy J. Morwessel; August 6 2007
- Diabetes Action: Understanding Your Test Results: Blood Sugar Testing / Management
- Legacy Health: High Blood Sugar After Meals: A Cause for Concern
- MayoClinic.com; Summary: Genetic Variation and the Pathogenesis of Type 2 Diabetes; Adrian Vella;
- Endocrineweb; Hyperglycemia: When Your Blood Glucose Level Goes Too High; Amy Hess-Fischl, Susan Spinasanta; August 25 2009
