A blood test measuring average blood sugar levels over the past 2-3 months by showing the percentage of hemoglobin bound to glucose.
FULL EXPLANATION
HbA1c (glycated hemoglobin) measures the percentage of hemoglobin proteins in red blood cells that have glucose attached. Because red blood cells live for about 120 days, HbA1c provides a picture of average blood sugar control over 2-3 months.
This test is valuable because it's not affected by day-to-day fluctuations in blood sugar and can be taken at any time without fasting. It's the primary test used to diagnose and monitor diabetes.
WHY IT MATTERS
HbA1c is one of the most important markers for metabolic health and is strongly associated with diabetes complications, cardiovascular disease, and all-cause mortality.
HOW TO IMPROVE
Lower HbA1c through consistent blood sugar management: regular exercise, balanced nutrition, weight management, medication adherence (if prescribed), and monitoring carbohydrate intake.
NORMAL RANGES
Normal: below 5.7%. Prediabetes: 5.7-6.4%. Diabetes: 6.5% or higher. Optimal for longevity: below 5.0-5.5%.
RELATED TERMS
Insulin
A hormone produced by the pancreas that regulates blood sugar by promoting glucose uptake into cells.
Blood Glucose
The concentration of glucose (sugar) in the blood, a critical marker of metabolic health and energy regulation.
Insulin Sensitivity
How effectively your cells respond to insulin to take up glucose from the bloodstream.
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Well-EstablishedThe rate at which your body burns calories at rest to maintain basic life functions.
Blood Glucose
Well-EstablishedThe concentration of glucose (sugar) in the blood, a critical marker of metabolic health and energy regulation.
Ketosis
Emerging ResearchA metabolic state where the body primarily burns fat for fuel, producing ketone bodies as an alternative energy source to glucose.