Biomarker % (mmol/mol)

HbA1c

Long-term blood sugar average over 2–3 months

Also known as

glycated hemoglobin hemoglobin A1c A1c long-term blood sugar

Definition

HbA1c (glycated hemoglobin) reflects the average blood glucose level over the preceding two to three months, as glucose binds reversibly to hemoglobin in red blood cells. It is the central diagnostic and monitoring marker for type 2 diabetes mellitus and prediabetes, and is also used in biohacking to track insulin sensitivity and the impact of dietary interventions.

Parameter Value
Unit % (mmol/mol)
Reference Range < 5.7% (normal) | 5.7–6.4% (prediabetes) | ≥ 6.5% (diabetes, ADA criteria)
Optimal Range (lab2go) < 5.4% (lab2go Optimum Zone)

Last Reviewed: 17 April 2026 · maritta