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Houston, TX
A 58-year-old male asked:

M58, my fasting blood sugar and a1c don't match, for example fasting is 150 and a1c is 5.7 why is it so? both done at one month interval.

2 doctor answers2 doctors weighed in
Dr. Dan Fisher
Internal Medicine 29 years experience
Looks good.: A1c integrates blood sugar values over the last 60 days whereas the fbg is just a simple point in time. The discordance suggests that your blood glucose is well controlled over the "rest" of the day.
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Dr. Stanley Schwartz
Endocrinology 54 years experience
A1c reflects: Average sugar for every second for 3months fingerstick sugar reflects blood sugar that 1 second in time :) so often they don't match.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Feb 5, 2014

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