Unpacking Your HbA1c: A Guide to Understanding Your Blood Sugar Snapshot

Understanding your HbA1c is a vital part of managing your health, particularly when it comes to diabetes. This simple blood test offers a clear picture of your average blood sugar levels over the past few months, helping both you and your healthcare team make informed decisions. So, let's break down what it all means for you. 

What Exactly is HbA1c? 

Think of your red blood cells as tiny couriers, carrying oxygen around your body. Attached to these couriers is a protein called haemoglobin. When glucose (sugar) is in your bloodstream, a certain amount of it sticks to this haemoglobin. This is called 'glycation'. The more glucose there is in your blood, the more it sticks. 

Since your red blood cells live for about 2 to 3 months, the HbA1c test measures the amount of glycated haemoglobin, giving you an average of your blood sugar control over that period. It's a much more reliable indicator of long-term blood sugar levels than a single finger-prick test, which only shows a snapshot at that specific moment [1].

Your HbA1c Numbers: What's Normal? 

In this country, HbA1c results are typically expressed in millimoles per mole (mmol/mol). Here's a general breakdown of what the numbers mean, according to health guidelines from organisations like Diabetes UK and the NHS [2, 3]: 

• Normal (Non-Diabetic): Below 42 mmol/mol. This indicates healthy blood sugar levels. 

• Pre-diabetes (Increased Risk of Type 2 Diabetes): Between 42 mmol/mol and 47 mmol/mol. If your HbA1c falls in this range, it means your blood sugar levels are higher than they should be, and you're at increased risk of developing type 2 diabetes. This is a crucial time to make lifestyle changes to prevent progression [3]. 

• Diabetes: 48 mmol/mol or higher. This level is diagnostic of diabetes [2, 3]. 

Important: While these are general guidelines, your individual target HbA1c, especially if you have diabetes, will be set by your healthcare team. Factors like your age, other health conditions, and risk of hypoglycaemia (low blood sugar) will be considered to determine the best target for you [2, 4]. For example, older adults or those with certain medical conditions might have a slightly higher target. 

Does Age Affect Normal HbA1c? 

For diagnosis, the HbA1c thresholds (e.g., 48 mmol/mol for diabetes) remain the same regardless of age. There isn't a different "normal" range for non-diabetic individuals based on age. However, as mentioned, for managing diabetes, healthcare professionals may adjust individual HbA1c targets for older patients to balance blood sugar control with avoiding potential risks like severe hypos [4]. 

When's the Best Time for an HbA1c Test? 

One of the great advantages of the HbA1c test is its convenience: you don't need to fast or prepare in any special way. You can have the test done at any time of day, making it easy to fit into your schedule [1]. 

If you have diabetes, your GP or diabetes team will usually arrange for you to have an HbA1c test every 3 to 6 months to monitor your blood sugar control. If your levels are stable, it might be tested less often, perhaps annually [4]. 

HbA1c Conversion Chart (mmol/mol to % and vice-versa) 

While mmol/mol is the standard here, you might sometimes come across results in percentages (%), particularly if looking at information from other countries. Here's a quick conversion guide, adapted from Diabetes UK resources, to help you understand both [1]: 

HbA1c (mmol/mol)	HbA1c (%)
31	5
37	5.5
42	6
48	6.5
53	7.0
59	7.5
64	8
69	8.5
75	9
80	9.5
86	10

Values in bold represent key diagnostic thresholds. 

What About the Cost of an HbA1c Test? 

If your HbA1c test is requested by your GP as part of your healthcare for diabetes management or risk assessment, then it will be free. 

However, if you wish to have a private HbA1c test, perhaps for personal monitoring or if you're concerned and don't meet standard referral criteria, the cost can vary. Private clinics and online home testing kits typically range from £20 to £95, depending on the provider and whether a consultation or additional blood draw fees are included. 

Why is Your HbA1c So Important? 

Knowing your HbA1c level empowers you to take control of your health. It helps: 

• Diagnose: Identify pre-diabetes and type 2 diabetes early [3]. 

• Monitor: See how well your diet, exercise, and medication are working to manage your blood sugar if you have diabetes [4]. 

• Prevent Complications: High HbA1c levels over time increase your risk of serious complications like heart disease, kidney problems, nerve damage, and vision loss. Keeping your HbA1c within your target range significantly reduces these risks [1, 4]. 

If you have any concerns about your blood sugar levels, or if you're due for a review, don't hesitate to speak to your GP or diabetes nurse. Taking a proactive approach to your HbA1c is a key step towards a healthier future. 

References 

[1] Diabetes UK. (n.d.). What is HbA1c?. Retrieved from https://www.diabetes.org.uk/about-diabetes/looking-after-diabetes/hba1c 

[2] NHS. (n.d.). High blood sugar (hyperglycaemia). Retrieved from https://www.nhs.uk/conditions/high-blood-sugar-hyperglycaemia/ 

[3] Forest Health Care. (n.d.). Prediabetes. Retrieved from https://foresthealthcentre.nhs.uk/services/self-help/prediabetes/ 

[4] National Institute for Health and Care Excellence (NICE). (2015, amended 2022). Type 2 diabetes in adults: management (NG28). Retrieved from https://www.nice.org.uk/guidance/ng28/chapter/recommendations