Capacity 01 · Regulate Energy
Signal · Fasting Insulin

The hormonal cost of keeping blood sugar normal.

A1c tells you what glucose is doing. Fasting insulin tells you what it cost to get there. You can have a "normal" fasting glucose only because your pancreas is working overtime to hold the line — and that strain shows up in insulin long before it shows up anywhere else.


The ranges that matter

The earliest line to cross.

Lab "normal" often runs up to 25 µIU/mL. That is a diagnostic ceiling, not a health target. Metabolically healthy people sit in the single digits. Your Radar scores every marker 0–100 on the same four-band continuum you see on your report: Fit (90+), Well (50–89), Short of well (26–49), Sick (25 and under). A score of 25 is the diagnosable line at any age. The values below are the age-40 reference — the bands shift with your age and sex, so use the calculator underneath for your own numbers.

Fit
≤ 4.9 µIU/mL
The body holds fasting glucose without much hormonal effort. Insulin sensitivity is intact.
Well
4.9 – 12.5 µIU/mL
Drifting. Still deep inside lab “normal,” but the pancreas is working harder than it should to keep glucose where it is.
Short of well
12.5 – 25 µIU/mL
The diagnosable line sits at 25, where the Radar scores 25. Compensatory hyperinsulinemia — glucose may still read normal, and that is the point.
Sick
≥ 25 µIU/mL
Sustained high hormonal cost. This is the earliest marker to move and one of the most responsive to coaching.
UnitµIU/mL
Test typeRequires a dedicated order (not default)
Fasting8–12 hours

What it reveals

Insulin is the volume knob.

Insulin's job is to move glucose out of the bloodstream and into cells. When cells stop responding — the first sign of insulin resistance — the pancreas compensates by producing more. Blood sugar stays in range, but the price has gone up.

This is why a person can have a perfectly normal A1c and a perfectly normal fasting glucose and still be metabolically compromised. The system is still producing the right output. It's just costing more hormonally to do it. You only see that cost if you measure the hormone.

Fasting insulin is the earliest lab marker to move when the Regulate Energy capacity begins to strain. Years before A1c drifts upward, insulin is already climbing. That lead time is what makes it one of the most valuable coaching signals you can have.

What to look for Rising fasting insulin with flat A1c means the body is compensating. Falling fasting insulin during a nutrition intervention — even with no weight change — means insulin sensitivity is recovering. That's often the first thing to move, and it's the most important thing to see move.

Coaches only

The intervention levers live with coaches.

The education above is open to everyone. The specific levers — what to actually do to move this marker — are part of the coaching program. Enter your coach password to unlock, or get in touch about becoming a coach.

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Coaching and education only. Not medical diagnosis or treatment.