Lab marker

Hemoglobin A1c (HbA1c)

HbA1c shows your average blood glucose over the last 2–3 months. It is the standard test for diagnosing and monitoring diabetes.

Common unit %
Adult reference range Normal <5.7%, prediabetes 5.7–6.4%, diabetes ≥6.5%

What it measures

When glucose circulates in your blood, a fraction of it sticks irreversibly to haemoglobin inside red blood cells — that's HbA1c. Because red blood cells live ~120 days, the HbA1c reading reflects average blood sugar across the previous 2–3 months and is much harder to game than a single fasting glucose. It is the WHO- and ADA-endorsed test for diagnosing and monitoring type 2 diabetes.

What a high value can mean

  • 5.7–6.4% — prediabetes (impaired fasting glucose). Lifestyle intervention reduces progression risk by 40–60%.
  • ≥6.5% — meets diabetes diagnostic threshold on confirmation.
  • >9% — poorly controlled diabetes; raises retinopathy, nephropathy and cardiovascular risk significantly.
  • >10% — endocrinology referral recommended.

What a low value can mean

  • Recent significant blood loss — replaces older glycated red cells with fresh ones.
  • Hemolytic anaemia — shortened red-cell lifespan reduces glycation window.
  • Recent transfusion — donor cells lower the average.
  • Hemoglobinopathies (sickle cell trait, thalassaemia) — some lab methods over- or under-read.

When to discuss with a doctor

HbA1c at or above 6.5% requires confirmation and prompt evaluation by your primary-care doctor. Between 5.7% and 6.4% is prediabetes — a window where structured exercise and dietary change reverse the trajectory in most patients. Mediora.AI calls out these thresholds with your last reading; consult a clinician before changing diabetes medication.

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