Body · lesson 2 of 11
Metabolic health — the early-warning panel
Glucose, HbA1c, insulin, HOMA-IR, and the trig/HDL ratio — catching insulin resistance early.
7 min read · reviewed October 2026
Metabolic markers are arguably the highest-value part of routine bloodwork, because the problems they catch are early and reversible — and astonishingly common. The core question they answer is: how well is your body handling sugar and insulin?
The metabolic markers, and what each one tells you
Your blood sugar after not eating (usually 8+ hours). A single snapshot — useful but easily nudged by stress, sleep, or a recent meal. Commonly cited optimal is on the lower end of normal; clinical 'prediabetes' typically starts around 100 mg/dL fasting (5.6 mmol/L). Exact cutoffs vary, so read it alongside HbA1c.
Glycated hemoglobin — the share of your red blood cells with sugar stuck to them. Because red cells live ~3 months, HbA1c is a roughly 90-day AVERAGE of blood sugar. Far harder to game than a one-morning glucose. Prediabetes is commonly cited at ~5.7%+ and diabetes at ~6.5%+.
Often the EARLIEST signal. To keep glucose normal, an insulin-resistant body quietly pumps out more insulin — so insulin can be high for years while glucose still looks fine. Many standard panels omit it; it's worth asking for.
A simple calculation combining fasting glucose AND fasting insulin into one insulin-resistance estimate. Catches the 'normal glucose, high insulin' state a glucose-only test misses. Lower is generally better.
Two numbers already on a standard lipid panel, divided. A high ratio is a widely-used, cheap PROXY for insulin resistance — no extra test required. (The ideal ratio differs by measurement units, so compare to the convention your lab uses.)
Insulin resistance is the silent, reversible one
Insulin resistance means your cells respond sluggishly to insulin, so your pancreas compensates by making more. It's the upstream driver behind type 2 diabetes and a major contributor to heart disease — but caught early (often via insulin or HOMA-IR before glucose moves), it responds strongly to diet, weight loss, sleep, and exercise. That's the whole reason to look early.
Roughly how many days of average blood sugar does a single HbA1c test reflect?
Somewhere between 7 and 180 days.
Reveal the answer →
~90 days (about 3 months)
HbA1c reflects roughly the previous ~90 days (about 3 months) because it measures sugar bound to hemoglobin in red blood cells, which live ~3 months. More recent weeks are weighted a bit more heavily. This is why HbA1c is a great trend marker — and why retesting it sooner than ~3 months rarely shows a real change.
What share of US adults are estimated to have prediabetes or diabetes — i.e. some degree of impaired blood-sugar handling? (general reference figure)
Somewhere between 5 and 80 %.
Reveal the answer →
Roughly half of US adults
This is a large and widely-cited figure: US public-health estimates commonly put adults with prediabetes alone in the broad range of ~30–40%+, and adding diagnosed plus undiagnosed diabetes pushes the combined share of impaired blood-sugar handling toward roughly half of adults. Estimates vary by source, definition, and year, and much of it is undiagnosed — so treat this as a 'this is extremely common' signal, not a precise statistic, and not a statement about you personally.
Record fasting glucose, HbA1c, and insulin over time so you can see the line — not just one dot — and tell a real change from day-to-day noise.