Current promotion
Insulin Resistance Testing: Fasting Insulin & Glucose Response
Go beyond fasting glucose, see how your insulin actually responds to a sugar load.
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Fasting insulin from $16.95; dynamic insulin response testing from $33.95 (promotional pricing at time of writing).
At a glance
Insulin resistance testing measures fasting insulin alongside glucose, and, in dynamic panels, how both respond to a standardized 75-gram glucose drink. It is designed for adults who want to catch shifts in insulin sensitivity before fasting glucose or HbA1c drift out of range. Options include a standalone fasting insulin test, a two-specimen glucose tolerance test, and a two-specimen insulin response to glucose test.
Best suited for
- People with normal fasting glucose who suspect early insulin resistance, post-meal energy crashes, stubborn weight gain, or waist-first fat storage
- Adults with a family history of type 2 diabetes or markers associated with PCOS or metabolic syndrome
- Low-carb, keto, or fitness-focused adults tracking how diet and training change their insulin sensitivity over time
- Anyone whose HbA1c is creeping upward and who wants a more detailed look at the insulin side of the equation
What's included
Insulin Test (Fasting)
Insulin Response to Glucose Test, 2 Specimens
Glucose Tolerance Test, 2 Specimens, 75g
Glucose Test (Fasting)
Hemoglobin A1c (HbA1c) Test
DH-4 Diabetes Health Panel (8 tests, 70 biomarkers)
DH-4 Diabetes Health Plus Panel (9 tests, 44 biomarkers)
Deep-dive the key markers: Fasting Glucose, HbA1c, Fasting Insulin
Key biomarker ranges
Commonly used adult reference ranges for markers this panel measures, labs vary, so always interpret results against your lab's stated ranges and with your doctor.
Commonly used reference ranges place fasting glucose at 70–99 mg/dL; results vary with sleep, stress, and recent illness, and labs differ slightly.
| Zone | Range |
|---|---|
| Low | 50–70 mg/dL |
| Optimal | 70–100 mg/dL |
| Prediabetic range | 100–126 mg/dL |
| Diabetic range | 126–160 mg/dL |
Commonly used reference ranges place HbA1c below 5.7%; conditions affecting red blood cells can skew results, so labs and clinicians interpret in context.
| Zone | Range |
|---|---|
| Optimal | 4–5.7 % |
| Prediabetic range | 5.7–6.5 % |
| Diabetic range | 6.5–10 % |
Commonly used reference ranges accept up to ~25 µIU/mL, but many clinicians view single-digit fasting insulin as the more informative target; assays vary by lab.
| Zone | Range |
|---|---|
| Low | 0–2 µIU/mL |
| Optimal | 2–10 µIU/mL |
| Above optimal | 10–25 µIU/mL |
| High | 25–30 µIU/mL |
The importance of testing
Insulin resistance often develops quietly: the pancreas compensates for declining insulin sensitivity by producing more insulin, which can keep fasting glucose looking normal for years. That is why a fasting insulin test, read alongside fasting glucose, is one of the earliest windows into how hard your body is working to keep blood sugar in range, a pattern associated with prediabetes, metabolic syndrome, and type 2 diabetes.
Dynamic testing adds a dimension a single fasting draw cannot. The two-specimen glucose tolerance test measures fasting and one-hour glucose after a 75-gram glucose drink, while the insulin response to glucose test compares fasting insulin with post-drink levels. Together they show how quickly glucose clears and how much insulin it takes to clear it, early insight into insulin sensitivity, beta-cell function, and carbohydrate metabolism.
For broader context, the DH-4 Diabetes Health panels bundle these dynamic tests with HbA1c, a comprehensive metabolic panel, a lipid panel, C-reactive protein, and urine microalbumin with creatinine, so you can see insulin function alongside the kidney, lipid, and inflammation markers that tend to shift with it.
The practical play is trend tracking: establish a baseline, retest after meaningful changes to diet, training, sleep, or weight, and bring the numbers to your doctor to discuss what they mean for your plan. Testing flags patterns to review, it does not replace medical evaluation.
Promo code
ULTA7E74Use promo code ULTA7E74 at checkout, current promotion; confirm final pricing and discount on the partner page.
Ready to get your numbers? Order online, visit a nearby draw site, and receive private results to review with your doctor.
Order NowFrequently asked questions
What is the best blood test for insulin resistance?
A fasting insulin test paired with fasting glucose is the most common starting point, because it shows how much insulin your body needs to hold glucose in range. Adding a two-specimen insulin response to glucose test or a glucose tolerance test gives a dynamic view of how your system handles an actual sugar load, which can surface changes a fasting draw alone may miss.
Can insulin resistance show up before blood sugar becomes abnormal?
Yes, the body often compensates for declining insulin sensitivity by producing extra insulin, which can keep glucose and even HbA1c in the normal range for years. Elevated fasting insulin or an exaggerated insulin response to glucose are earlier markers associated with that compensation, and they are results to review with your doctor rather than a medical conclusion.
Can I order insulin resistance testing without a doctor's visit?
Yes, these tests are sold direct-to-consumer, so you can order online through the partner page and complete your blood draw at a local lab location without booking a doctor's appointment first. Results come to you, and flagged values are worth discussing with your physician.
Is this testing available in all US states?
No, direct-to-consumer lab testing is restricted or prohibited in New York, New Jersey, and Rhode Island, so residents of those states may be blocked at the partner's checkout. Residents of other states can typically order online and test at a nearby draw location.
How do I prepare for insulin and glucose response testing?
Plan to fast, typically 8 to 12 hours with water permitted, before fasting insulin, fasting glucose, and glucose tolerance testing. The two-specimen tests also involve a timed second draw after you drink a standardized glucose solution, so allow extra time at the lab and follow the preparation instructions provided when you order.
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