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Sacramento, CA
A 60-year-old female asked:

I'm pre diabetic so check often. when i went for blood work, i tested at home and my fasting glucose was 88. three hours later at lab was 106. still fasting. why the variation in readings?. my meter is within the parameters of the strips?

2 doctor answers2 doctors weighed in
Dr. Arnold Lentnek
Dr. Arnold Lentnekanswered
Infectious Disease 54 years experience
Home glucometers are inexpensive, easy to use and readily available. Not especially accurate. Will give you a general range of your blood glucose (eg., it IS 120 and definitely NOT 320). But small variations one reading to another is routine. Also, “real” blood glucose constantly fluctuates based on eating, exercise, metabolic state.Variations like you describe are meaningless
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Gurmukh Singh
Pathology 50 years experience
Glucometers test whole blood. Lab tests plasma. Plasma levels are more reliable and are the method on which the diagnostic criteria are based.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Sep 4, 2021
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