# HbA1c

HbA1c (glycated hemoglobin) reflects the proportion of hemoglobin stably bound to glucose, providing an integrated estimate of average blood glucose over approximately the prior 2 to 3 months, with the most recent ~30 days contributing roughly half of the signal per published kinetic models. It is the primary biomarker for diagnosing and monitoring type 2 diabetes (threshold 6.5%) and prediabetes (5.7 to 6.4%). HbA1c is influenced by erythrocyte lifespan, anemia, and hemoglobin variants.

## Sources

- DCCT Research Group. (1993). The Effect of Intensive Treatment of Diabetes on the Development and Progression of Long-Term Complications in Insulin-Dependent Diabetes Mellitus (DCCT). New England Journal of Medicine. https://doi.org/10.1056/NEJM199309303291401

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_Canonical: https://longevity-germany.com/en/glossary/hba1c · Part of Longevity Cities · Updated 2026-01-15_