TirzTom said:

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

Glycemic variability as the key metric for glycaemic control success: my coefficient of variation (CV) on CGM dropped from 35% to 22%. 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.

A1cHero_PHX 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.

Patient selection optimization for glycaemic control: emerging predictive biomarkers for GLP-1 agonist response include:

The 4-week early responder criterion is the most clinically actionable: if you haven't lost ≥3% by week 4 at a therapeutic dose, discuss optimization strategies with your provider.

VendorMark said:

Glycemic variability as the key metric for glycaemic control success: my coefficient of variation (CV) on CGM dropped from 35% to 22%.

My labs after 3 months on glycaemic control: A1C 6.2%, fasting glucose 87 mg/dL, fasting insulin 4 uIU/mL. My endo says these are "textbook perfect."

For context, my baseline A1C was 6.9% and fasting glucose was 122 mg/dL. The improvement has been dramatic and consistent.

One thing that is still open after sarah.morrison’s answer:

How would you tell the difference between that and the alternative explanation?

paige_pharma said:

My labs after 3 months on glycaemic control: A1C 6.2%, fasting glucose 87 mg/dL, fasting insulin 4 uIU/mL.

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 = 5.3 (insulin resistant) → Current = 1.5 (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.