Reasons for High HbA1c Level



High HbA1c levels are often commonly witnessed in people with diabetes. However, if you are diagnosed with high levels of HbA1c in your blood with no diabetes history, there might be some reasons for the same.

Knowing the reasons for high A1C levels helps you understand your health condition better. This way, you can consult your doctor for medications and make appropriate changes in your diet and lifestyle. Read this blog to know the benefit of taking the HbA1c test and the top reasons for high A1C levels in non-diabetic people.

What is HbA1c Test?

The hbA1c test, A1C test or haemoglobin A1C, is the common blood test that shows the average blood sugar (glucose) level for the past three months. This glycated haemoglobin or glycosylated haemoglobin test measures the glucose stuck to your red blood cells or haemoglobin. This test is usually used to diagnose prediabetes or diabetes health conditions.

Though high HbA1c levels are seen majorly in diabetic patients, you might be at risk of developing high levels of HbA1c even if you do not own a history of diabetes. Several lifestyle factors, including age, gender, diet, etc., can affect HbA1c levels.

If you are over 45 or are under 45 but with medical conditions or symptoms mentioned here, you might need an A1C test to diagnose your condition. If your A1C test results showed high HbA1c levels, these might be the possible reasons for the same.

Why Do You Need HbA1c Test?

The hbA1c test is required for people suffering from the following symptoms such as:

  • Numb hands or feet
  • Dry skin
  • Fatigue
  • Weight loss without effort
  • Unusually high appetite
  • Blurred vision
  • Frequent urination
  • Slow healing sores
  • Multiple infections

These are some common symptoms observed in patients with high levels of HbA1c. If you have experienced any symptoms, it is safe to take an HbA1c test to stop the worsening of the condition.

The A1C test is also helpful in managing diabetes in Type 2 diabetic patients. However, if you are under 45 with the following medical conditions, an HbA1c test is recommended to curtail or slow down the development progress of diabetes.

  • Prediabetes
  • Obese or overweight
  • High blood pressure and cholesterol
  • Family history of diabetes
  • History of heart stroke or other heart disorders
  • Sedentary lifestyle – physically active for less than three times a week
  • PCOS (Polycystic ovary syndrome)
  • Gestational diabetes

The A1C test is also recommended for people over 45 years of age to enable close monitoring of the patient's condition. People over 45 can take the A1C test according to their health conditions and A1C results.

  • If your A1C test results are normal, it is recommended to repeat it every 3 weeks
  • If A1C results show the prediabetic range, you need to be tested every 1 – 2 years
  • The A1C test is required at least twice a year to manage your condition and treatment if you have diabetes.

There is no special preparation needed to take an A1C test. The test takes a blood sample from a finger stick or your arm. The A1C test process is simple and takes less time. Book your HbA1c test easily at MediBuddy, India's largest digital healthcare platform.

How to Interpret HbA1c Test Results?

The A1C test shows the percentage of red blood cells (RBC) having glucose-coated haemoglobin. Every person possesses some percentage of haemoglobin coated with sugar in their RBC. However, if this percentage is high, this leads to high HbA1c levels. A1C results are different for every patient.

A1C level depends on your age, health conditions, lifestyle, and other factors. It is best to approach your doctor and discuss your A1C results for better clarity and understanding.

However, here are the commonly considered A1C levels to diagnose prediabetes or diabetes in most patients.

A1C Levels 

A1C Percentage Range 

Normal HbA1c level 

Below 5.7% 

Prediabetic A1C levels  

5.7% - 6.4% 

Diabetic A1C levels 

6.5% or above 

Normal HbA1c Level:

The Normal HbA1c level should be below 5.7%. This indicates that your A1C levels are healthy. However, it is recommended to maintain an active lifestyle and a healthy diet to keep your A1C levels in control.

High HbA1c Levels:

This includes prediabetic and diabetic A1C ranges, where people with high A1C levels are likelier to develop diabetes.


This health condition indicates high blood sugar but is not high enough to be treated as diabetes. Since prediabetes often goes symptomless, it is highly recommended to take an A1C test. The prediabetic A1C levels range from 5.7% - 6.4%. If the test results are close to 6.4%, the patient is likelier to develop diabetes.


People with A1C levels of 6.5% or above are considered diabetic. In this case, informing your doctor will be the best practice, as diabetes often results in further health complications. The A1C result for managing diabetes can also be seen in eAG (mg/dL) numbers on your blood sugar monitor.

A1C %

eAG mg/dL









What Are the Reasons for High HbA1c Levels?

Maintaining Normal HbA1c levels and checking the pattern of your A1C levels is crucial to find any unusual changes. High A1C levels are often associated with diabetes. However, if your test results came out to be high levels of A1C even though you do not have diabetes, these might be some of the common reasons.


The effects of age on high A1C levels are considered in the new studies. These studies are researched on non-diabetic people with normal sugar levels. The association of glycation with ageing might be the reason for high A1C levels. Though age is not the sole reason, it is one of the contributing factors to high A1C.


People with iron or vitamin B12 (folate) deficiency anaemia show high A1C levels. These deficiencies increase HbA1c levels irrespective of blood sugar levels. Anaemic people, often women, witness their HbA1c levels being frequently high. Bleeding, gut disorders, lack of nutrient absorption, and other non-dietary reasons keep the A1C high.

Low Thyroid Hormone Levels:

People with underactive thyroid or hypothyroidism often experience low thyroid hormone levels responsible for causing a boosted level of HbA1c. Thyroid hormones control metabolic rate and the rate of your body's calorie-burning capacity. The thyroid hormone levels in the blood affect the A1C level.

Spleen Disorders:

Elevating your A1C levels is often associated with spleen disorders like sickle cell or asplenia. These A1C levels can also be falsely elevated following the splenectomy (spleen removal process).

Kidney or Liver Disorders:

A1C test accuracy alters for people suffering from kidney disorders that cause other health disorders like anaemia, malnutrition, and kidney failure. People with liver diseases find it hard to rely on the A1C test as it is not an exact predictor of glycemic control.


Overweight people tend to have impaired glucose tolerance and insulin resistance. These conditions are reported to be linked to high A1C.

Certain Medications:

Over-counter drugs like aspirin, when taken excessively, and chronic overuse of certain medications might lead to inaccurate A1C readings or errors. The high doses of antioxidants are also the reason for inflated HbA1c.

Other Possible Causes:

In addition to the common reasons mentioned above, high A1C can also cause due to various other health conditions, such as:

  1. Chronic stress
  2. Sleep disorders
  3. Smoking and alcoholism
  4. Alteration of supplements


If you experience or see a rise in your A1C levels, it is always better to consult your doctor along with the required modifications in your diet, lifestyle, and medications. Though most of the time, A1C test results show an accurate reading of HbA1c level, conditions related to the spleen and anaemia interfere with the A1C levels. It is highly recommended to maintain Normal HbA1c levels to avoid the supplementary health disorders caused by diabetes.