Fasting Glucose
Blood sugar after at least 8 hours without calories, in mg/dL. Optimal range: Below 100 mg/dL is normal; 100-125 mg/dL is impaired fasting glucose; 126 mg/dL and above (confirmed) is diabetes.
What it measures
Blood sugar after at least 8 hours without calories, in mg/dL. A snapshot of overnight glucose regulation by the liver.
Why it matters
Fasting glucose is a first-pass screen for dysglycemia, but a weak stand-alone screen for early insulin resistance; normal fasting glucose can coexist with high insulin. Pair with HbA1c and fasting insulin.
Optimal ranges
Sourced targets, not just lab reference ranges. Lab ranges describe the population; these describe where the evidence says you want to be.
| Range | Context |
|---|---|
| Below 100 mg/dL is normal; 100-125 mg/dL is impaired fasting glucose; 126 mg/dL and above (confirmed) is diabetes | American Diabetes Association criteria, summarized by Mayo Clinic. |
How to improve it
- 1
Same levers as HbA1c: fewer refined carbs, post-meal walks, resistance training
- 2
Consistent sleep, since poor sleep raises morning glucose
- 3
Limit late-night eating
Connected to
Goals
Ingredients
Longevity Lab Report
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Educational information, not medical advice. Talk to your doctor before acting on any biomarker result.