The HbA1C test is a blood test frequently used in screenings to monitor and assess blood sugar levels in people with diabetes. Unlike a fingerstick glucose meter or a blood glucose test, which provides information about current blood sugar levels, the HbA1C test provides information about the average blood sugar level over a specific period in the past. It is a particularly important part of treatment and follow-up for people with diabetes.
HbA1C is known as the glycated hemoglobin test, which reflects the average blood sugar level over the past 2–3 months. A high level of glycated hemoglobin in the blood is a significant indicator that blood sugar levels have been elevated for an extended period. For people with well-controlled diabetes, an annual HbA1C test may be sufficient; however, for those with elevated test results or who are unable to maintain blood sugar control, the test may need to be repeated at more frequent intervals, such as every 3 or 6 months. Even a slight elevation in HbA1C levels indicates the potential for serious complications. For this reason, the test must be performed regularly without interruption, and the results must be carefully reviewed by a doctor.
How Does the HbA1C Test Work?
Hemoglobin is the protein that gives blood its red color. In people with high blood sugar, glucose binds to hemoglobin, forming glycated hemoglobin. This binding occurs because the body is unable to properly utilize the glucose in the blood and transport it to tissues. The amount of glucose binding to hemoglobin proteins is directly related to the current blood sugar level. Hemoglobin produced in the body has an average lifespan of 2–3 months. Therefore, measuring the HbA1C level in the blood provides the average blood sugar level over a 2–3-month period. Because HbA1C reflects the average blood sugar level over a specific period, it is much more accurate than other blood sugar tests. In healthy individuals without diabetes, approximately 5% of the hemoglobin in the blood is glycated. A slightly elevated result on the hemoglobin A1C test may indicate prediabetes, while a significantly higher result may indicate diabetes.
What Should HbA1C Levels Be?
In healthy individuals without diabetes, blood HbA1C levels are expected to fall within the range of 4.7% to 5.6%. If the hemoglobin A1C level is found to be between 5.7% and 6.4%, there is a possibility of having prediabetes, also known as “hidden diabetes.” At this stage, fluctuations in blood sugar levels may be at a level that cannot be detected by fasting blood sugar tests or fingerstick glucose tests. In individuals diagnosed with diabetes, the HbA1C level is greater than 6.5%.
Chronic conditions or certain medications being taken can affect the results of the HbA1C test. Conditions such as kidney failure, liver disease, or anemia—which directly affect hemoglobin levels in the blood—can lead to inaccurate test results. The same applies to certain medications being taken. For this reason, before the test is administered, it is important to know whether the patient has any other chronic conditions and what medications he is taking.
How Can HbA1C Be Lowered?
The only way to lower this level is to ensure proper blood sugar control. Therefore, treatment plans for people with diabetes must first be clearly defined by a specialist, and patients should be referred to dietitians to determine appropriate medications or develop a suitable nutrition plan. Diabetes education should be provided in detail by multidisciplinary teams consisting of specialists, nurses, and dietitians, and patients should be educated on carbohydrate counting.
In patients with Type 2 diabetes, after diagnosis and blood sugar regulation, the period during which the patient’s blood sugar levels remain within normal limits without taking specific medication is referred to as the remission phase. This condition can be observed. During this process, patients must be kept under constant monitoring for their blood sugar levels, and they must be provided with the necessary training on how to perform fingerstick blood glucose tests at home.
HbA1c Results
HbA1c test results are reported as a percentage. The higher the HbA1c percentage, the greater the risk of developing diabetes and its complications. However, if your HbA1c test result is 6.5% or higher, you may have diabetes.