Blood Sugar & Metabolism
How your body handles sugar and energy: glucose, A1c, insulin and related hormones.
13 tests explained
Most common tests
- GlucoseGlucose is the sugar in your blood and your body's main fuel. This test shows how much is there at the moment the sample is drawn.
- Hemoglobin A1c (HbA1c)A1c shows your average blood sugar over about the past 2 to 3 months, based on how much glucose is stuck to your hemoglobin.
- InsulinInsulin is the hormone that moves sugar from your blood into your cells. This test shows how much is in your blood, usually after fasting.
Common follow-up tests
- Beta-Hydroxybutyrate (BHB)Beta-hydroxybutyrate (BHB) is the main ketone your body makes when it burns fat for fuel. It rises with fasting, low-carb eating or too little insulin.
- C-PeptideC-peptide is released along with insulin, so it shows how much insulin your own pancreas is making, even if you take insulin.
- Estimated Average Glucose (eAG)eAG restates your A1C in the same units as a glucose test, to show roughly what your average blood sugar has been over about 3 months.
- FructosamineFructosamine measures sugar-coated proteins in your blood, mostly albumin, and reflects your average blood sugar over the last 2 to 4 weeks.
- Glucose (1-Hour, 50 g Challenge Screen)A first-step sugar test in pregnancy. Your blood sugar one hour after a 50 g sugar drink shows whether a longer test is needed.
- Glucose (2-Hour Postprandial)Your blood glucose about 2 hours after you start a normal meal. It shows how well your body handles the sugar and starch from food.
- Glucose, OGTT 1-HourBlood glucose one hour after a measured sugar drink in an oral glucose tolerance test. In pregnancy, a high 1-hour value is one criterion for gestational diabetes.
- Glucose, OGTT 2-HourBlood glucose two hours after a 75 g sugar drink. It is the main OGTT value used to sort glucose tolerance into normal, prediabetes and diabetes ranges.
- Glucose, OGTT 3-HourBlood glucose three hours after a 100 g sugar drink. It is the last value of the 3-hour glucose tolerance test used in pregnancy.
- HOMA-IRA calculated score that estimates how well your body responds to insulin, using a fasting glucose and a fasting insulin from the same blood draw.