Normal blood glucose (sugar) and HbA1C
What is normal blood glucose (sugar)?
Normal human blood sugar = 4-6 mmol/L – and less than 8 mmol/L, two hours after a meal.
What about haemoglobin A1C (HbA1C) test?
Normal HbA1C is 20-41 mmol/mol (or 4-6%).
The haemoglobin A1C test (HbA1C) measures your average blood sugar level over the last 3 months. This test doesn’t require fasting and can be done any time.
How are prediabetes and diabetes diagnosed?
By testing your blood sugar and HbA1C levels.
Blood glucose in prediabetes and diabetes
- Normal human blood sugar = 4-6 mmol/L
- Prediabetes is diagnosed if your random blood sugar = 7-11 mmol/L (twice)
- Diabetes is diagnosed if you have a random blood sugar > 11 mmol/L (or a fasting blood sugar > 7 mmol/L) (twice)
HbA1C in prediabetes and diabetes
Normal HbA1c = 20-41 mmol/mol (or 4-6%)
- Prediabetes is diagnosed if your HbA1c = 42-47 mmol/L (6-6.5%) (twice)
- Diabetes is diagnosed if your HbA1c = 48 mmol/mol or over (>6.5%).
HbA1C mmol/mol and %
Confusingly HbA1c comes in 2 different units. Mmol/mol is the more modern unit. These are the equivalent values.
42 mmol/mol = 6.0% = prediabetes
48 = 6.5 = diabetes
53 = 7
59 = 7.5
64 = 8
75 = 9.
Diabetes UK has a converter to convert HbA1C from mmol/mol to %, and vice versa.
Monitoring of DM in adults (and target HbA1Cs)
42 mmol/mol or lower
Summary
We have described what is a normal blood glucose (sugar) and HbA1C. We hope it has been helpful.
Other resources
Here is more information on blood glucose, HbA1c and definitions of DM
10 important blood tests and normal values
