Understand your HbA1c: blood sugar under control
The HbA1c test is one of the most important tests for monitoring blood sugar levels and detecting diabetes at an early stage. Unlike single blood sugar measurements, it provides insight into the average blood glucose concentration over the past 2–3 months, allowing for a long-term assessment of blood sugar control. Whether for prevention, monitoring, or adjusting treatment – the HbA1c test plays a crucial role in preventive healthcare. This blog covers all the essential information about the HbA1c test, including how it works, normal and elevated values, and why and for whom the test is particularly relevant.
Table of Contents
- What is the HbA1c test?
- Why is the HbA1c test important?
- Normal and elevated HbA1c values
- Who should take the test?
- When and how often should the HbA1c test be performed?
- Are there factors that can affect HbA1c results?
- What is the difference between an HbA1c test and a blood glucose test?
- Summary
What is the HbA1c test?
The HbA1c test is a blood test that measures the average blood glucose level over the past 8–12 weeks. It analyzes how much sugar (glucose) is bound to hemoglobin, a component of red blood cells. The HbA1c value (long-term blood sugar) is expressed as a percentage or in millimoles per mole (mmol/mol) and is also known as the A1c test (MedlinePlus, 2022).
How is the HbA1c test performed?
The HbA1c test is quick and simple to perform: a small blood sample is taken – either from a vein at a doctor’s office or via a finger prick at home with a home test kit. The sample is analyzed in a laboratory, where the percentage of glycated hemoglobin (HbA1c) is measured. The test requires no preparation and can be carried out at any time of day, regardless of meals.
Why is the HbA1c test important?
The HbA1c test is essential for the prevention, diagnosis, and treatment of diabetes. It provides an overview of average blood glucose levels and enables long-term evaluation of blood sugar control. Here are the key reasons:
- Prevention and early detection: The test helps identify prediabetes or diabetes early, often before symptoms appear, reducing the risk of complications such as cardiovascular issues, kidney and nerve damage.
- Long-term monitoring: Unlike a single blood glucose reading, the HbA1c test shows how blood sugar levels have been over an extended period.
- Treatment monitoring: People with diabetes can use the test to track and adjust their treatment in consultation with their doctor.
- Independent of meals: The test is simple and flexible, as it is not affected by short-term fluctuations.
- Monitoring during pregnancy: In pregnant women with gestational diabetes, the HbA1c test can help keep blood sugar levels in check over time and minimize risks for both mother and child.
Source: Cleveland Clinic, 2022
Normal and elevated HbA1c values
The HbA1c value indicates how much sugar is permanently bound to the hemoglobin in the blood. The higher the value, the poorer the blood sugar control. Certain values are considered normal, while elevated values may indicate prediabetes or diabetes. The table below shows the classification of HbA1c values and their significance:
| HbA1c value (%) | HbA1c value (mmol/mol) | Meaning |
|---|---|---|
| Below 5.7% | Below 39 mmol/mol | Normal blood sugar level |
| 5.7% – 6.4% | 39 – 47 mmol/mol | Prediabetes (increased risk of diabetes) |
| 6.5% or higher | 48 mmol/mol or higher | Diagnosis: Diabetes mellitus |
The classification of HbA1c values may vary slightly depending on the laboratory or the medical guidelines used (DiabetesUK, 2024).
Who should take the test?
The HbA1c test is a vital tool for long-term monitoring of blood sugar levels, early detection of diabetes, and treatment adjustment. It is especially important for certain risk groups and individuals with existing health concerns.
- People with prediabetes: Individuals diagnosed with prediabetes should regularly take an HbA1c test to monitor the effectiveness of lifestyle changes such as healthy eating and exercise.
- People with diabetes: For those already diagnosed with diabetes, the test is essential to track blood sugar control and evaluate treatment.
- People at high risk for prediabetes and diabetes: This includes individuals who are overweight, have high blood pressure, a family history of diabetes, or lead an unhealthy lifestyle.
- Pregnant women: Pregnant women with gestational diabetes or at increased risk for the condition should be tested to ensure blood sugar control during and after pregnancy.
- People with hormonal disorders: Conditions like polycystic ovary syndrome (PCOS) or certain thyroid disorders can increase the risk of diabetes and make regular testing advisable.
- People taking certain medications: Some medications, such as corticosteroids or drugs used to treat high blood pressure, can affect blood sugar levels and increase the risk of developing diabetes.
Regular HbA1c testing helps identify health risks early and enables effective prevention or treatment (MacGill, 2023).
When and how often should the HbA1c test be performed?
The frequency of HbA1c testing depends on individual circumstances and health status. The following general recommendations apply:
| Group | Recommended Frequency |
|---|---|
| People without diabetes | Every 1–3 years if risk factors are present (e.g., overweight, family history). |
| People with prediabetes | At least once a year to monitor and prevent progression to diabetes. |
| People with diabetes | Every 3 months if blood sugar is unstable or treatment is being adjusted. Every 6 months if blood sugar is stable and well controlled. |
| Pregnant women | At the beginning of pregnancy and every 4–6 weeks if diabetes or risk factors are present. |
Source: American Diabetes Association, 2014
Are there factors that can affect HbA1c results?
Yes, various factors can influence the accuracy of HbA1c values. Conditions that affect the lifespan of red blood cells – such as anemia, hemoglobinopathies (genetic disorders like sickle cell anemia), or chronic kidney disease – can either increase or decrease HbA1c levels. Vitamin B12 deficiency or iron deficiency can also affect the result. Certain medications, including corticosteroids or specific antihypertensives, may have an impact as well. Additionally, significant blood loss or recent blood transfusions can lead to inaccurate results. Therefore, it is important to interpret the HbA1c value in the context of individual health and in conjunction with other laboratory results.
(DiabetesUK, 2024).
What is the difference between an HbA1c test and a blood glucose test?
An HbA1c test measures the average blood glucose level over the past 2–3 months, while a blood glucose test measures the current level of sugar in the blood at a specific moment. The HbA1c test provides a long-term overview, whereas a blood glucose test reflects short-term fluctuations, for example after meals or in a fasting state. Both tests complement each other to provide a complete picture of blood sugar control.
Do you want to get tested?
With the HbA1c blood sugar test from Homed-IQ, you can conveniently test your HbA1c level from the comfort of your home – simple, discreet, and reliable.
In addition to this test, Homed-IQ offers other tests that target common risk factors. The heart disease blood test helps you better understand your cardiovascular health by measuring key biomarkers such as cholesterol and inflammation levels. The weight balance test analyzes metabolic markers such as insulin and thyroid hormones, which are critical for weight and metabolism. All tests are analyzed in ISO-certified laboratories. Start today and gain valuable insights into your health – no doctor’s visit required!
Summary
The HbA1c test measures the average blood glucose level over the past 2–3 months and provides a long-term assessment of blood sugar control, making it a key tool for the prevention and monitoring of diabetes. Unlike a blood glucose test, which measures the current blood sugar level at a specific moment, the HbA1c test reflects long-term trends and helps avoid short-term fluctuations such as those occurring after meals. The test is particularly relevant for people with diabetes, prediabetes, and risk factors such as being overweight or having a family history of diabetes, as it helps monitor blood sugar control and guide treatment. Various factors can influence test results, which is why they should always be interpreted alongside other lab values and individual health status.
