Do disappointing blood glucose results make you feel like a failure? Don’t let them. They aren’t report cards, and you can’t pass or fail. These numbers are not there to hurt you, but to help direct you.

Laura Menninger, a comedian known as the “Glucose Goddess,” says this about her meter:

“If I were climbing Mount Everest and I was 30 degrees S.E. of where I needed to be, I wouldn’t sit and say, ‘Oh, I stink at this! I give up!’ I would correct my course and continue on. Your meter just tells you where you’re at, so you can take corrective action in order to reach your goal. No room for guilt. Just do what you can do.”

Your blood glucose meter

Home blood glucose meters are not always accurate—they have a 10–15 percent error rate or greater if the results are extremely high or low. Fortunately, they do a superb job of highlighting trends. Are you higher at a certain time of day? Are you lower at other times? Knowing this information helps you adjust your diabetes regimen. The following are popular blood checking times and suggested ways to interpret the results:

In the morning

Suggested goal: 90–130 mg/dl

Your blood glucose level at this time can be affected by nighttime hormonal surges, the state of your health (maybe you have an infection or a cold), physical activity you’ve done during the past 24–48 hours and any medications you’ve taken.

Immediately after eating

A blood check at this time has little use. Your body needs time to digest the food before you observe its effect on blood glucose levels.

Two hours after eating

Suggested goal: less than 180 or 160 mg/dl

Check two hours after the first bite of a meal. If your level is higher than desired, either your carbohydrate servings were too large or your medication dose was inadequate for that meal. Alcohol usually causes a drop in blood glucose levels, but a sweetened drink, such as a sweet wine or piña colada, can cause them to climb.

After exercise

Physical activity normally lowers blood glucose levels for several hours afterward. But, if you don’t have adequate insulin in your system during the activity, your blood glucose level may climb instead. Many experts recommend checking before, during and after prolonged activity in order to catch changes in blood glucose levels as they occur. Treat high and low levels as recommended by your healthcare provider.

A high result at any time can be caused by

• Inadequate or outdated medication
• Too much food
• Not enough physical activity
• Illness
• Menopause and menstrual cycles
• Glucose monitor error (outdated strips, etc.)
• Stress

A low reading can be caused by

• Inadequate food
• Too much physical activity
• Monitor error
• Too much medication
• Menopause and menstrual cycles

Blood glucose data can help you improve your diabetes control. Take advantage of the information provided by your meter, and use it wisely.