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Fasting glucose test
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A fasting glucose test takes a snapshot of how much glucose is in the blood after at least eight hours without food or drinks other than water. Glucose is a type of sugar and a primary source of energy for the body.
It is a snapshot of one moment, not a movie spanning several months. Hemoglobin A1c estimates a longer-term average and does not require fasting. A fasting glucose test measures glucose; one number alone does not establish a diagnosis.
In brief
A fasting glucose test measures the concentration of glucose, the sugar that serves as a primary energy source, in a blood sample taken after at least eight hours without food or drinks other than water.
This result reflects glucose at a single point in time after fasting. It is not the same as hemoglobin A1c, which estimates average glucose over the preceding months and does not require fasting. This overview defines the test but does not interpret individual values or establish a diagnosis.
Sources (1)
- MedlinePlus, U.S. National Library of MedicineBlood Glucose Test
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
Updated