glucose · INS
Fasting Insulin
The hormone that moves glucose into cells. Elevated fasting insulin can be one of the earliest signs that the body is working harder to keep blood sugar normal (insulin resistance), often years before glucose or HbA1c rise.
This page is general wellness education, not medical advice. Your own lab’s reference range and your clinician’s interpretation always take precedence.
Typical reference range
| Group | General range |
|---|---|
| Adults | Typical fasting range ~2.6–25 uIU/mL (lab-dependent) |
Optimal-band note: Many metabolic-health practitioners consider fasting insulin under ~10 uIU/mL favorable; higher-normal values can be an early sign of insulin resistance before glucose rises. Soft target, not a diagnostic cutoff.
Units: uIU/mL. Ranges vary by lab and assay — read yours against the range printed on your own report.
What high Fasting Insulin can mean
- Insulin resistance
- Excess body fat
- High refined-carb diet
- Inactivity
- Some medications
What low Fasting Insulin can mean
- Type 1 diabetes
- Pancreatic insufficiency
- Prolonged fasting