If diabetes runs in your family, your risk is elevated. You probably already know this. What you may not know is what to ask for.
Most people wait for symptoms — thirst, fatigue, blurred vision. By the time those arrive, blood sugar has been quietly high long enough to have already caused damage. Screening before symptoms isn't anxious over-testing. It's the most useful five-minute blood draw you can have.
Here are the four tests worth knowing about — and what to say at the appointment.
1. HbA1c — your three-month average
Your red blood cells live for about three months. Glucose sticks to them as it passes through. The HbA1c test counts how many cells have sugar attached, giving you an average across that whole window.
One reading. No fasting needed. Probably the single most useful piece of metabolic information you can have about yourself.
What the numbers mean:
- Below 42 mmol/mol: normal
- 42-47: prediabetes — the reversible grey zone
- 48 or above: type 2 diabetes (confirmed on a second test)
How to ask: "Can I have an HbA1c? Diabetes runs in my family and I'd like a baseline."
2. The lipid panel
This isn't strictly a diabetes test, but it belongs in the same conversation. The early signature of insulin resistance often shows up as: high triglycerides, low HDL ("good cholesterol"), shifted LDL pattern. This trio sometimes appears before HbA1c moves.
Plus, diabetes and heart disease travel together. If you've got prediabetes plus poor lipid numbers, your overall cardiovascular risk is higher than either number alone suggests.
How to ask: "Can we add a fasting lipid panel to the same draw?" It's efficient — same fast, same needle.
3. Fasting glucose
This measures the sugar in your blood after eight hours without food — the level your body maintains overnight. Useful because it shows your baseline: what your body looks like when no meal is in play.
- Below 6.0 mmol/L: normal
- 6.1-6.9: impaired fasting glucose
- 7.0 or above: diabetes (confirmed)
Often bundled with the lipid panel since both need the same fast. Two birds, one breakfast skipped.
4. The glucose tolerance test (when needed)
This one is more involved. You arrive fasting, drink a sweet solution, and have your blood drawn two hours later. It measures how quickly your body clears a sugar load — a more sensitive test of early insulin resistance than HbA1c.
Not a first-line test for everyone. Worth asking for if HbA1c comes back borderline or you're concerned about gestational diabetes risk. Your doctor will know whether to use it.
What to actually say
You don't need all four at once. The most useful combination is HbA1c + lipid panel + fasting glucose. A clean script:
"My parent (or sibling) has type 2 diabetes. I'd like an HbA1c and a fasting lipid panel to set a baseline. I'm happy to fast for a morning appointment."
Most doctors will agree without hesitation. If the results are normal, repeat every 3-5 years. If they're borderline, you've caught the window where small habits make the biggest difference.
The goal isn't to find something wrong. It's to know your starting point — so that if anything drifts, you spot it early. That's when intervention works best.
Curiosity first. — Dr. Brugal