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Diabetes Monitoring

Using Your iHealth Meter

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Why Do I Get a Different Blood Sugar Reading?

Jingze Tian, MS, RD
3
May 29, 2021

If your home blood glucose meter is giving you a result differing from your expectations, from another meter, or from one blood drop to another, then you may wonder about the meter’s accuracy.

There are plenty of factors that may affect the reading: cleanliness of your hands, test strips, food intake, checking time, stress, medications may all be culprits.

Factors that Exaggerate Blood Sugar Results

Factor

Possible Results

Dehydrated or anemia

False high

Residue on the skin (lotion, hand cream, food, etc.)

False high

Water on the hand

False low

Over massage the finger

False low

Not enough blood applied to the test strip

False low

Test Strip is expired/exposed to heat or moisture

False high or low

Glucose meter is exposed to heat or moisture

False high or low (or no number generated)

Medication/Supplement

Certain medication/supplements may affect the blood sugar reading, either higher or lower

Physical stress: sick, injured

Physical stress may increase your blood sugar

Exercise

Exercise may briefly increase your blood sugar

Questioning Meter Accuracy: 

If you question the accuracy about your iHealth glucose meter, you can

Compare with your A1C

  • If you see your blood sugar has changed over a period of time (3 months), maybe the A1C can validate your concern. A1C is a reflection of the 3-month average blood sugar levels.
  • Please ask your Care Team or your doctor for more information.

Compare with Lab Results

  • Lab results are the “gold standard” to check the blood sugar accurately. Home monitors can only estimate the blood sugar level.
  • You can take the blood glucose meter along with you when you get your next lab work done. Check your blood sugar level with your meter at the same time that blood is drawn for lab tests. Then compare your meter’s reading with the lab results. Results that are within 15% of the lab reading are considered accurate.

Compare against a Control Solution

  • Follow your normal blood-testing procedure, but use the control solution instead of blood. The acceptable range is labeled on the bottle of your test strip.
  • If a control solution test falls within the range, the accuracy is confirmed.
  • If the result is out of the range, please try again with a new, unopened vial of test strip.
  • Let your Care Team know about the testing results.

Don’t Compare One Blood Glucose Meter to Another.

  • Each blood glucose meter uses different technology to estimate a blood sugar reading.
  • Consistently use one meter and monitor the overall trend.
  • If you want to validate your own glucose meter, you can get a control solution for your own device (usually can be found in local pharmacy for common brand).
  • Check out this article about Glucometers and Clinically Approved Precision to learn more about the glucose meters.

Please contact your Care Team if you have any question. You can read this article to learn more about the tips of getting an accurate blood sugar reading.