BenResearch_OR said:

A1C went from 7.4 to 5.6 over nine months and my prescriber was more interested in the fasting insulin, which I did not expect.

Insulin sensitivity test (HOMA-IR) on glycaemic control — arguably the most important metabolic marker most people aren't tracking:

HOMA-IR = (fasting insulin × fasting glucose) ÷ 405

My numbers: Baseline HOMA-IR = 5.6 (insulin resistant) → Current = 1.0 (insulin sensitive)

Anything above 2.0 indicates insulin resistance. The goal is below 1.5. GLP-1 agonists address the root metabolic dysfunction, not just the symptoms. This is why they work so much better than calorie restriction alone.

Dr.RenalNash said:

Insulin sensitivity test (HOMA-IR) on glycaemic control — arguably the most important metabolic marker most people aren't tracking: HOMA-IR = (fasting…

Fasting insulin is the lab my functional medicine doctor cares about most for glycaemic control: it's a much earlier marker of metabolic dysfunction than glucose or A1C.

My fasting insulin: 31 → 15 → 6 uIU/mL over 9 months. Target is <7. By the time your fasting glucose is elevated, your insulin has been elevated for YEARS trying to compensate.

Ask your doctor to include fasting insulin in your bloodwork panel. It's cheap (~$20) and incredibly informative.

BenResearch_OR said:

A1C went from 7.4 to 5.6 over nine months and my prescriber was more interested in the fasting insulin, which I did not expect.

This is my experience too, for whatever a second data point is worth.

Adding the clinical framing, because it changes how the question reads.

My labs after 3 months on glycaemic control: A1C 5.1%, fasting glucose 91 mg/dL, fasting insulin 8 uIU/mL. My endo says these are "textbook perfect."

For context, my baseline A1C was 7.7% and fasting glucose was 126 mg/dL. The improvement has been dramatic and consistent.