Glucose
Your blood sugar level after an overnight fast.
What is it
Fasting glucose measures blood sugar after at least 8 hours without food. It is a standard marker for screening of diabetes and prediabetes.
Why it's measured
Fasting glucose is foundational to evaluating metabolic health and has been associated with cardiometabolic risk across published research.
Reference range
Standard laboratory reference
< 100 mg/dL
Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.
What results may indicate
Elevated
Values in the prediabetes (100–125 mg/dL) or diabetes (≥126 mg/dL) range have been associated with elevated cardiometabolic risk and warrant clinical follow-up.
Lower
Very low fasting glucose can warrant clinical evaluation depending on context.
These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.
When it's measured
Part of routine metabolic panels and physicals.
Related markers
Common questions
Fasting glucose measures blood sugar after at least 8 hours without food. It is a standard marker for screening of diabetes and prediabetes.
It's one of the markers used to build a fuller picture of your health. On its own it tells you very little, so it's most informative when reviewed alongside related markers.
It's measured from a standard blood draw at Quest or LabCorp. Fasting Glucose is one of the markers included in the OPTML Apex Panel, where your results are read across systems and reviewed by a U.S.-licensed physician.
Reference ranges vary by laboratory, and a single value rarely tells the whole story. Review your result with a physician in the context of your other markers, symptoms, and history.
Fasting Glucose is one signal among many. Answer a few quick questions and we’ll point you to the panel that fits.
Measured in
A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.
Explore the Apex Panel →This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.