Blood sugar monitoring is an essential part of diabetes care. Find out when to test your blood sugar level, how to handle poor results and more.
When you have diabetes, managing your blood sugar level is the most important thing you can do to feel your best and prevent long-term complications. Consider it an opportunity to take charge of your health.
Know your target range
Your doctor will set your target blood sugar range. For many people who have diabetes, target levels are:
- Before meals — between 90 and 130 milligrams per deciliter (mg/dL), or 5 and 7 millimoles per liter (mmol/L), also known as your fasting blood sugar level
- One to two hours after meals — lower than 180 mg/dL (10 mmol/L)
- Before bedtime — between 110 and 150 mg/dL (6 and 8 mmol/L)
Remember that your target blood sugar range may differ, especially if you're pregnant or you develop diabetes complications. Your target blood sugar range may change as you get older, too. Sometimes reaching your target blood sugar range is a challenge. But the closer you get, the better you'll feel.
When to test your blood sugar
How often you need to test your blood sugar level depends on the type of diabetes you have and your individual diabetes treatment plan.
If you have type 1 diabetes, your doctor may recommend testing your blood sugar level at least three times a day — perhaps before and after certain meals, before and after exercise, and before bed. You may need to check your blood sugar level more often if you're ill or you change your daily routine.
If you take medication — with or without insulin — to manage type 2 diabetes, your doctor may recommend testing your blood sugar level once a day. If you manage type 2 diabetes with diet and exercise alone, you may need to test your blood sugar level even less often.
How to test your blood sugar
To test your blood sugar level, you'll need a blood sugar monitor. Some monitors are large with easy-to-handle test strips, while others are compact and easier to carry. Some monitors track the time and date of each test, the result and trends over time. You may even be able to download this information to your computer.
Most blood sugar monitors require you to prick your fingertip with a special needle (lancet). Some lancets allow you to adjust the prick depth to accommodate differences in skin thickness.
If you wonder which type of blood sugar monitor would be best for you, ask your doctor or diabetes educator for a recommendation. Keep in mind that your insurance provider may limit coverage to specific types of monitors.
Troubleshooting problems with your blood sugar monitor
When used correctly, you can count on your blood sugar monitor to provide accurate readings. If you think something's not right, start with the basics:
- Check the test strips. Throw out damaged or outdated strips.
- Check the monitor. Make sure the monitor is at room temperature, and the strip guide and the test window are clean. Replace the batteries in the monitor, if needed.
- Check the measurement scale (calibration). Some monitors must be calibrated to each container of test strips. Be sure the code number in the monitor matches the code number on the container of test strips.
- Check your technique. Wash your hands with soap and water before pricking your finger. Apply a generous drop of blood to the test strip. Don't add more blood to the test strip after the first drop was applied.
If you're still not sure what's wrong, do a quality control test according to the manufacturer's instructions and check the owner's manual for other troubleshooting issues. You can bring the monitor to your next doctor appointment as well.
What to do with poor results
Record the results of each blood sugar reading, whether you jot the results in a log or your monitor keeps track for you. If your blood sugar readings are consistently higher or lower than your target range — or blood sugar extremes don't respond to adjustments in diet or medication — you may need to revise your treatment plan. In some cases, your doctor may suggest changing your diet or including more physical activity in your daily routine. If that's not effective, you may need to take medication or adjust your medication dosage.