Why test insulin levels along with glucose and A1C?

Insulin testing provides early detection of metabolic dysfunction that glucose and A1C tests might miss. Insulin resistance often develops years before blood sugar levels become abnormal, making this combination valuable for identifying prediabetes risk and monitoring metabolic health trends over time.

How long do I need to fast before this test?

Fasting for 8-12 hours is required for accurate glucose and insulin measurements. You may drink water during this time, but avoid all food, beverages with calories, and smoking. Morning appointments are recommended to minimize fasting discomfort and ensure accurate results.

Can this test diagnose diabetes definitively?

While this panel includes the standard tests used for diabetes diagnosis, clinical diagnosis typically requires confirmation with repeat testing or additional tests. The results provide valuable information about diabetes risk and metabolic health that should be discussed with a healthcare provider for proper interpretation.

What if my glucose is normal but insulin is high?

This pattern often indicates insulin resistance, where your pancreas produces extra insulin to maintain normal blood glucose levels. This is considered an early warning sign of metabolic dysfunction and may suggest increased risk for developing type 2 diabetes in the future.

How often should I repeat this diabetes risk panel?

For individuals with normal results and no risk factors, testing every 3 years may be appropriate. Those with prediabetes results or significant risk factors may benefit from annual testing. People with previous abnormal results should follow up according to their healthcare provider's recommendations, typically within 1-2 years.

Do medications affect these test results?

Yes, certain medications can influence glucose, A1C, and insulin levels. Diabetes medications, steroids, and some blood pressure medications may affect results. However, you should continue taking prescribed medications as usual unless specifically instructed otherwise by your healthcare provider before testing.

Heart & Diabetes

Diabetes Risk Panel (Glucose + A1C + Insulin)

A comprehensive diabetes screening panel that measures glucose, hemoglobin A1C, and insulin levels to assess diabetes risk and metabolic health.

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What this test measures

This comprehensive diabetes risk panel measures three key biomarkers that work together to provide a complete picture of metabolic health and diabetes risk. The hemoglobin A1C test measures average blood glucose levels over the past 2 to 3 months, offering insight into long-term glucose control. Fasting blood glucose measures sugar levels in blood and is a simple and common way to screen for prediabetes, diabetes or gestational diabetes. The insulin test measures the amount of insulin hormone in the bloodstream, which is crucial for understanding how well the body regulates blood sugar.

Together, these tests can identify different aspects of glucose metabolism dysfunction. While glucose and A1C tests are standard for diabetes diagnosis, adding insulin provides valuable insight into early metabolic changes. Insulin levels are usually out of order long before there are abnormalities in blood sugar levels, which is why a blood sugar test might come back completely normal even if you are suffering from insulin resistance. This makes the combination particularly valuable for detecting prediabetes and insulin resistance before they progress to type 2 diabetes.

What's included

Fasting Glucose - measures blood sugar levels after fasting

Hemoglobin A1C - measures average blood glucose over 2-3 months

Fasting Insulin - measures insulin hormone levels after fasting

Who should consider this test

You might consider this test if you are experiencing any of the following:

Individuals with family history of diabetes who want early detection of metabolic changes
Those experiencing symptoms like increased thirst, frequent urination, unexplained fatigue, or blurred vision
People with risk factors such as being overweight, physically inactive, or having high blood pressure
Adults over 35 seeking comprehensive diabetes screening as part of preventive healthcare
Individuals with previous borderline glucose results who need more detailed metabolic assessment
Those interested in understanding their insulin sensitivity and overall metabolic health

What to expect

Preparation

Fasting for 8-12 hours is required before testing (no food or drinks except water). Medications should be taken as prescribed unless otherwise directed by a healthcare provider. Schedule the appointment for morning hours to minimize fasting discomfort.

Sample Type

A standard blood draw from a vein in the arm, requiring only one blood sample for all three tests.

Collection

The blood collection process takes just a few minutes at any participating lab location. A trained phlebotomist will draw the blood sample using standard sterile techniques. No doctor visit required.

Turnaround

Results are typically available within 1-2 business days and will be sent securely through the patient portal or by email.

Understanding your results

The diabetes risk panel provides three complementary measures of glucose metabolism. A1C test results are reported as a percentage, with higher percentages indicating higher blood glucose levels over the past two to three months. Fasting glucose is measured in mg/dL and reflects blood sugar levels after an overnight fast. Insulin levels are measured in microunits per milliliter (μU/mL) and indicate how much insulin the pancreas is producing. Together, these results help healthcare providers assess current glucose control, long-term trends, and early signs of insulin resistance that may not yet show up in glucose measurements alone.

Population	Reference Range	Notes
Adults - Fasting Glucose	70-99 mg/dL (Normal), 100-125 mg/dL (Prediabetes), ≥126 mg/dL (Diabetes)	Based on American Diabetes Association diagnostic criteria
Adults - Hemoglobin A1C	<5.7% (Normal), 5.7-6.4% (Prediabetes), ≥6.5% (Diabetes)	Reflects average blood glucose over 2-3 months
Adults - Fasting Insulin	2-25 μU/mL (Laboratory range), <10 μU/mL (Optimal range)	Lower levels generally indicate better insulin sensitivity

Reference ranges shown are general guidelines. Your lab report will include the specific reference range used by the laboratory that processed your sample, which is the authoritative range for interpreting your results.

What does a “Low” result mean?

Low glucose levels may indicate hypoglycemia, which can cause symptoms like dizziness, shakiness, or confusion and may require medical attention. Low insulin levels may suggest type 1 diabetes or advanced type 2 diabetes, where the pancreas produces insufficient insulin to regulate blood sugar. Low A1C levels are generally favorable, though extremely low levels combined with low glucose and insulin might indicate underlying pancreatic dysfunction or other metabolic conditions. Healthcare providers will consider all three measurements together along with symptoms and medical history to determine appropriate follow-up care.

What does a “High” result mean?

Elevated results may indicate various stages of glucose metabolism dysfunction. If A1C levels are between 5.7% and 6.4%, this indicates prediabetes range, while levels of 6.5% or higher suggest diabetes. Fasting glucose levels of 100-125 mg/dL typically indicate prediabetes, meaning blood sugar levels are higher than normal but not high enough to be classified as diabetes. High insulin levels may suggest insulin resistance, where the pancreas produces extra insulin to maintain normal blood glucose levels. High insulin levels can indicate insulin resistance, a precursor to type 2 diabetes, where the body's cells do not respond effectively to insulin. These patterns often develop years before clinical diabetes diagnosis.

Privacy & confidentiality

All test orders are authorized and results reviewed by an independent, board-certified physician who is not the patient's personal doctor. Your diabetes risk panel results are completely confidential and protected by strict privacy regulations. This testing is conducted entirely outside of your regular healthcare system, which means results are not reported to your doctor unless you specifically choose to share them. The test results are not part of your medical records and will not appear on insurance statements or explanation of benefits. Your employer, insurance company, or other third parties cannot access this information. All communication regarding your results is sent directly to you through secure, encrypted channels. This private testing approach allows individuals to understand their metabolic health status without concerns about potential impacts on insurance coverage or medical record documentation. You maintain complete control over who has access to your diabetes risk assessment information.

Frequently asked questions

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CPT Code: 82947, 83036, 83525

This test may not be available in: NY, NJ, RI

This page is for informational purposes only and does not constitute medical advice. Always consult with a healthcare provider regarding any health concerns. LevelPanel does not diagnose, treat, or prescribe.

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