Dr.NephBHM_UK 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 = 5.4 (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.

LipidDoc_ATL 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: 22 → 14 → 7 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.

Dr.NephBHM_UK 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.

Same experience, arrived at from the opposite direction.

From the other side of the consultation, briefly.

Glycemic variability as the key metric for glycaemic control success: my coefficient of variation (CV) on CGM dropped from 41% to 18%. Target is <36%, with <30% being ideal.

Why this matters more than average glucose: large glucose swings cause oxidative stress, endothelial damage, and promote advanced glycation end-products (AGEs). A flat glucose line at 95 mg/dL is metabolically healthier than oscillating between 60 and 160, even if the average is the same.