What Is the Normal HbA1C Level?

HbA1C stands for hemoglobin A1C, which is a blood test that measures a person’s average blood sugar levels over the past 3 months. It is also sometimes called an A1C test. 

What Does the A1C Test Measure?

When sugar enters the bloodstream, it attaches to a protein in the red blood cells called hemoglobin. People with higher blood sugar levels such as diabetics have more sugar attached to their hemoglobin. 

The HbA1C test measures the percentage of the red blood cells that have sugar-coated hemoglobin.

What Are HbA1C Levels Used For?

Measurement of HbA1C is used to diagnose prediabetes and diabetes. 

HbA1C levels are also used to help manage diabetes. 

What Can Affect an HbA1C Level?

Aside from prediabetes and diabetes, factors that can falsely increase HbA1C levels include:

• Anemias associated with decreased red cell turnover
• Removal of the spleen
• Renal failure
• Severe high triglycerides (hypertriglyceridemia)
• Severe hyperbilirubinemia
• Chronic alcohol consumption
• Chronic salicylate use (found in certain foods and medications)
• Chronic opioid use
• Lead poisoning

Factors that can falsely decrease HbA1C levels include:

• Anemia from acute or chronic blood loss
• Enlarged spleen
• Pregnancy
• Vitamin E ingestion
• Ribavirin and interferon-alpha use

Factors that can either falsely increase or decrease HbA1C levels include:

• Red blood cell transfusion
• Hemoglobin variants
• Vitamin C ingestion