Question 1

What does HbA1c actually measure?

Accepted Answer

When sugar molecules in your blood stick to haemoglobin (the oxygen-carrying protein in red blood cells), they form HbA1c. Because red blood cells live about 120 days, HbA1c reflects your average blood sugar over the last 2–3 months — unaffected by what you ate this morning.

Question 2

Do I need to fast for an HbA1c test?

Accepted Answer

No. That's one of its main advantages over the older fasting glucose test — you can eat and drink normally before the blood draw. HbA1c gives a picture of your long-term blood-sugar control regardless of your most recent meal.

Question 3

What HbA1c range is considered normal?

Accepted Answer

Under 5.7% (39 mmol/mol) is normal. 5.7–6.4% (39–47 mmol/mol) is prediabetes — a warning zone where lifestyle changes can often reverse the trend. 6.5% (48 mmol/mol) or higher on two tests indicates diabetes.

Question 4

Can I lower my HbA1c?

Accepted Answer

Yes — often substantially. Losing 5–10% of your body weight, cutting refined carbohydrates and sugary drinks, walking 30+ minutes daily, and improving sleep and stress can all move HbA1c down. People in the prediabetes range who make these changes can often return to normal within 3–6 months.

Question 5

Can anything give a misleading HbA1c result?

Accepted Answer

Yes — conditions that shorten or lengthen the life of red blood cells (haemolytic anaemia, recent blood loss, iron-deficiency anaemia, some haemoglobin variants common in African, Mediterranean, and South-East Asian populations) can skew HbA1c. If your doctor suspects one of these, they may use fructosamine or a continuous glucose monitor instead.

HbA1c (IFCC)

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