DIABETES · 5 MIN READ
Understanding your HbA1c: what the number really means
HbA1c is the single most useful number in diabetes care. Here is what it measures, what your target should be, and how to bring it down.
What is HbA1c?
Sugar in your blood sticks to haemoglobin, the protein inside red blood cells. Because red blood cells live for about three months, HbA1c — the percentage of haemoglobin with sugar attached — reflects your average blood sugar over the past two to three months.
That makes it more reliable than a single fasting reading, which can change from day to day with food, sleep and stress.
What do the numbers mean?
• Below 5.7% — normal.
• 5.7% to 6.4% — prediabetes. Your risk of diabetes is raised, but lifestyle change can often bring it back to normal.
• 6.5% or above, confirmed on a repeat test — diabetes.
For most adults already living with diabetes, the target is below 7%. Your doctor may set a slightly higher target if you are older, have frequent low sugars or other health conditions — targets should always be personal.
Why HbA1c and daily readings sometimes disagree
Your glucometer shows your sugar at one moment; HbA1c shows the average. If your fasting readings look good but your HbA1c is high, your sugars are probably rising after meals or overnight.
HbA1c can also read falsely high or low in anaemia, after recent blood loss or a transfusion, in pregnancy and in some kidney conditions. If your result does not match how you feel or your home readings, tell your doctor.
KEY TAKEAWAYS
How to bring your HbA1c down
- Check it every three months Until you reach your target, then every six months.
- Test after meals, not just fasting A reading two hours after your largest meal shows what your food is doing.
- Walk after meals A 10–15 minute walk after lunch and dinner measurably lowers post-meal sugar.
- Take your medicines consistently Missed doses are one of the commonest reasons for a rising HbA1c.