HbA1c: normal range and what it means
Your average blood sugar over ~3 months.
Normal range
Adult reference range.
- Optimal< 5.4 %
- Normal5.4 – 5.7 %
- Pre-diabetic5.7 – 6.5 %
- Diabetic≥ 6.5 %
What it measures
The percentage of haemoglobin coated with sugar — a 3-month average of your blood glucose.
What moves it
Overall diet quality, glucose spikes, and red-blood-cell turnover.
How to bring it into range
The same habits that steady glucose: fibre, movement after meals, sleep, and limiting refined carbs.
How fast it responds
Slowly — reflects ~90 days, so changes show over months.
Also reported as: glycated hemoglobin · a1c · hba1c
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Common questions
- What is a normal HbA1c level?
- Optimal: < 5.4 %. Adult reference range.
- What does a high HbA1c mean?
- A value above the reference band means HbA1c is outside the range typical for a healthy adult. A single reading is rarely conclusive on its own — what matters is the trend across draws and the other markers around it, which is why HealthOS reads the whole panel together rather than one number at a time.
- How do I improve my HbA1c?
- The same habits that steady glucose: fibre, movement after meals, sleep, and limiting refined carbs.
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More in Metabolic
Reference ranges are general-population guidance compiled from common clinical laboratories, not a diagnosis. Lab-to-lab ranges differ. Always read your results with your doctor.