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Can a HbA1c test diagnose diabetes?
The HbA1c test can be used as a way of diagnosing diabetes, particularly cases of prediabetes and type 2 diabetes.
The World Health Organisation (WHO) suggests the following diagnostic guidelines for diabetes:
- HbA1c below 42 mmol/mol (6.0%): Non-diabetic
- HbA1c between 42 and 47 mmol/mol (6.0–6.4%): Impaired glucose regulation (IGR) or Prediabetes
- HbA1c of 48 mmol/mol (6.5%) or over: Type 2 diabetes
If your HbA1c test returns a reading of 6.0–6.4% that indicates prediabetes, your doctor should work with you to suggest appropriate lifestyle changes that could reduce your risk of developing type 2 diabetes.