Good to knowOne result rarely tells the whole story. Your provider looks at your results together with your symptoms, exam, and other tests.
What the test is
It helps tell type 1 from type 2 diabetes and investigate low blood sugar.
Why it's done
- Unclear type of diabetes
- Repeated low blood sugar without a clear cause
Getting ready and what happens
- You may be asked to fast.
How the test is done
- A health worker cleans the skin, puts a band around your arm, and draws blood from a vein with a small needle. It takes a few minutes.
What the results mean
Low
Suggests the body makes little insulin, as in type 1 diabetes.
High
Can occur with insulin resistance, type 2 diabetes, or, rarely, an insulin-making tumor.
Questions to ask your provider
- What do my results mean for me?
- Do I need to repeat this test or have other tests?
Risks
A blood draw is very safe. You may have slight pain or a small bruise where the needle went in.
Related conditions
Related tests
Sources
Last updated 2026-11-13.