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METABOLIC BIOMARKER

Fasting Glucose

Fasting Plasma Glucose

Single-snapshot glucose control measure — sensitive to acute stress but foundational for metabolic tracking.

STANDARD RANGE
<100 mg/dL (normal); 100–125 (prediabetes); ≥126 (diabetes)
OPTIMAL (OPTIMIZATION)
70–89 mg/dL is the metabolic-optimization target

What Fasting Glucose Measures

Fasting plasma glucose is the classic glycemic marker — a single fasted measurement of blood sugar. Unlike HbA1c, which reflects 90-day average, fasting glucose captures current state and is sensitive to acute factors: overnight fast quality, stress response, recent sleep, last evening meal.

Optimal targets are lower than the "normal" cutoff — <90 mg/dL is a reasonable optimization aim, especially in a longevity context. Values 100–125 indicate prediabetes; >126 on two occasions meets diabetic threshold.

Single measurements can mislead (one bad night's sleep or an unusually stressful morning can bump the number 10 points). Trend matters more than any single draw.

What Affects This Biomarker

Fasting glucose is influenced by: chronic carbohydrate load and insulin sensitivity, acute factors (last night's sleep, morning cortisol, stress, alcohol the prior evening), adiposity, fitness, and pharmacologic agents — GLP-1s and metformin reliably lower it; growth hormone peptides and exogenous HGH can raise it modestly.

In the Context of Peptide Protocols

Monitor fasting glucose at baseline and every 3 months on GLP-1s (expect decline), GH peptides / HGH (watch for drift above 95), and MK-677 (particular attention here). Pair with fasting insulin to compute HOMA-IR for a complete insulin-sensitivity picture.

Peptides That Commonly Move Fasting Glucose

Semaglutide
GLP-1
Tirzepatide
GLP-1
Retatrutide
GLP-1
MK-677
Growth
MOTS-c
Anti-Aging

Related Reading

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Informational only — not medical advice. Reference ranges vary by lab and individual context. Work with a licensed provider to interpret your specific results.