Serum Glycated Hemoglobin (HbA₁c) by Immunoassay
This test measures the percentage of hemoglobin molecules that have been attached to sugar (glycated), reflecting your average blood sugar levels over the past 2–3 months.
["Helps track long-term blood sugar control for diabetes management."]
Key facts at a glance
- LOINC
- 85044-6
- Short code
- SA glyco resist Pnl Islt
- Synonyms
- SA glyco resist Pnl Islt
- Category
- glucose
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What Is HbA₁c Used For?
HbA₁c is primarily used to diagnose diabetes, assess how well your blood sugar is managed over time, and guide treatment decisions. It’s a key indicator of whether your diabetes medications or lifestyle changes are effective.
How Is HbA₁c Different from Fasting Blood Sugar?
Unlike a single fasting blood sugar test, HbA₁c provides a broader picture of your average glucose levels, accounting for daily fluctuations. It’s less affected by short-term stress or recent meals.
Why Might My HbA₁c Test Be Done?
Your doctor may order an HbA₁c test if you have diabetes, prediabetes, or if you’re at risk for diabetes (e.g., due to obesity, family history, or high blood pressure). It’s also used to monitor chronic conditions like kidney disease or heart disease linked to diabetes.
What Could Affect My HbA₁c Results?
Several factors can influence HbA₁c, including recent blood loss (e.g., from surgery or heavy periods), severe anemia, or certain medications (like blood thinners or chemotherapy drugs). Always discuss your full medical history with your provider.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
HbA₁c is a critical tool for diabetes care because it reflects long-term blood sugar control. Targets vary by individual, but values above 6.5% often signal diabetes, while values below 5.7% are typically considered normal. Regular monitoring helps prevent complications like nerve damage, eye disease, or heart problems.
Short name
HbA₁c
Frequently asked questions
How often should I get an HbA₁c test?
Can HbA₁c be affected by diet or exercise?
What if my HbA₁c is higher than expected?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy