If you’re managing diabetes or are at risk, you’ve likely heard of the HbA1c test (also known as the A1c test). But what does this number actually mean? Unlike a finger-prick test that gives you a snapshot of your glucose at one moment, an HbA1c test provides the big picture of your average blood sugar over two to three months.
HbA1c: Your 3-Month Blood Sugar Report Card
The HbA1c test measures your average blood sugar levels over the past two to three months by checking the percentage of hemoglobin in your red blood cells that has glucose attached to it. The more glucose you have in your bloodstream, the higher the percentage will be.
- Haemoglobin: A protein in your red blood cells that carries oxygen.
- Glycation: When glucose in your bloodstream sticks to haemoglobin, it becomes "glycated."
The higher your blood sugar levels have been, the more glycated haemoglobin you'll have. An HbA1c test result is given as a percentage (e.g., 6.5%) or in mmol/mol (e.g., 48), which is the international standard unit used widely in Europe.
Why is HbA1c So Important?
This test is the gold standard for diagnosing prediabetes and diabetes and for assessing how well a person's diabetes is being managed over time. It helps you and your doctor understand if your management plan is working.
Interpreting Your HbA1c Results
The following ranges are based on European guidelines that are widely accepted by key health bodies, including the UK's National Institute for Health and Care Excellence (NICE) and the International Diabetes Federation (IDF).
| HbA1c Level | Result |
| Below 42 mmol/mol (6.0%) | Normal |
| 42 to 47 mmol/mol (6.0% to 6.4%) | Prediabetes (increased risk of developing Type 2 diabetes) |
| 48 mmol/mol (6.5%) or above | Diabetes |
* For the official clinical guidelines on diagnosing and managing diabetes, including HbA1c thresholds, you can refer to the UK's National Institute for Health and Care Excellence (NICE) website: NICE Guidelines - Diabetes.
HbA1c vs. Daily Monitoring: Understanding the Difference
You might wonder: if you monitor your blood sugar every day, why is the HbA1c test still important?
- HbA1c: This test is your long-term report card. It shows your average control over months, helping you and your doctor assess your long-term risk for complications.
- Daily Monitoring (BGM or CGMS): This is your real-time feedback. It helps you make immediate decisions about food, exercise, and medication to keep your levels stable from day to day.
Think of it this way: daily monitoring helps you steer the car, while the HbA1c test shows you if you're on the right road to your destination.
How Continuous Glucose Monitoring System(CGMS) Helps
A CGMS like LinX Vista bridges the gap between these two tests. While you still need the HbA1c lab test, CGMS provides a detailed picture of what happens between tests. It shows:
- Glucose trends (are you spiking after meals?).
- Time in Range (what percentage of the day you spend in your target zone?).
This data empowers you to make precise adjustments to your lifestyle, ultimately helping you lower your HbA1c and reduce health risks.
Ready to see the full story of your glucose levels? LinX Vista CGMS provides the actionable insights you need to complement your HbA1c test and take control. Explore LinX CGMS Technology.