Key Takeaways

  • A1C measures your average blood sugar over roughly three months; Diabetes Canada puts prediabetes at an A1C of 6.0% to 6.4%, while the ADA and CDC use a wider 5.7% to 6.4% range.
  • Prediabetes usually has no symptoms, but it sharply raises the risk of type 2 diabetes, heart disease and stroke — and most people who have it don't know.
  • In the NIH's Diabetes Prevention Program, structured lifestyle change — losing 5% to 7% of body weight and getting 150 active minutes a week — cut progression to type 2 diabetes by

Your Blood Test Says You're Not Diabetic. So Why the Warning?

Your blood test comes back. One number is flagged.

A1C. Slightly high.

Your doctor says you're not diabetic — but you're not quite in the clear either.

Welcome to prediabetes, the awkward middle ground where your blood sugar is higher than normal but hasn't reached type 2 diabetes.

Here's the unsettling part: you could have it for years without knowing.

The CDC says prediabetes usually has no symptoms. Most people who have it don't even realize it.

But there's good news hiding in that warning. This is a stage where changing your habits can make a remarkable difference.

What Your A1C Is Actually Telling You

Think of A1C as your blood sugar's report card for the past three months.

Glucose sticks to hemoglobin, the oxygen-carrying protein inside your red blood cells. Since those cells live for roughly three months, the A1C test measures the percentage of hemoglobin with glucose attached.

Unlike a fasting glucose test, which measures your blood sugar after at least eight hours without food, A1C doesn't require fasting.

And one bad week barely changes the result.

It's the bigger picture, not yesterday's dessert.

Canada and the U.S. Don't Agree on the Warning Line

Here's something many Canadians don't realize.

The same A1C result can be labelled differently depending on which country's guidelines you use.

Under Diabetes Canada:

  • 5.5%–5.9%: Increased risk, worth monitoring.
  • 6.0%–6.4%: Prediabetes.
  • 6.5% or higher: Diabetes threshold.

Prediabetes can also mean fasting glucose of 6.1–6.9 mmol/L or a two-hour glucose tolerance result of 7.8–11.0 mmol/L. The fasting glucose threshold for diabetes is 7.0 mmol/L.

But the American Diabetes Association and CDC start the prediabetes range at 5.7%, continuing through 6.4%. Their fasting glucose range is 100–125 mg/dL (5.6–6.9 mmol/L).

So imagine your A1C comes back at 5.8%.

In Canada? Increased risk.

In the U.S.? Prediabetes.

Same blood. Same number. Different warning label.

Neither guideline is necessarily wrong. They simply draw the line for intervention at different points.

The Risk Isn't Just Diabetes

Prediabetes doesn't mean you're destined to develop type 2 diabetes.

But ignoring it isn't harmless either.

The CDC links prediabetes with increased risk of type 2 diabetes, heart disease and stroke.

And one finding cited in Diabetes Canada's guidelines is especially striking.

In the cited study, people with both impaired fasting glucose and an A1C of 6.0%–6.4% progressed to type 2 diabetes at a rate of 100% over five years.

That's a finding from a particular study group — not a prediction that everyone with those results will develop diabetes.

Still, two warning signs together deserve attention.

The CDC identifies several risk factors: being overweight, being 45 or older, having a parent or sibling with type 2 diabetes, exercising fewer than three times weekly, a history of gestational diabetes, and polycystic ovary syndrome.

Diabetes Canada recommends screening every three years starting at age 40, or earlier and more frequently when risk factors are present.

The Part That Should Give You Hope

Here's where the story changes.

You don't necessarily need a dramatic transformation to lower your risk.

The U.S. National Institutes of Health studied 3,234 adults at high risk in its Diabetes Prevention Program.

Over approximately three years, an intensive lifestyle program reduced the development of type 2 diabetes by 58% compared with placebo.

For participants aged 60 and older, the reduction reached 71%.

And the lifestyle goals weren't extreme.

  • Lose 5%–7% of body weight if you're overweight. For someone weighing 200 pounds, that's approximately 10–14 pounds.
  • Get at least 150 minutes of physical activity weekly. Think brisk walking for 30 minutes, five days a week.

No marathon required.

Just consistent changes that produced meaningful results in a major clinical trial.

The Twikup Take

Prediabetes is a warning you might never feel.

No obvious symptoms. No dramatic moment. Just a number on a blood test that could change what happens next.

And while prediabetes can already be associated with health risks, the encouraging part is that progression isn't inevitable.

A major clinical trial found that modest weight loss and regular movement could reduce diabetes risk by more than half.

So if your A1C falls between 5.7% and 6.4%, don't assume everything is fine — and don't assume diabetes is inevitable either.

Know your A1C, understand which guideline applies, and make a plan before your next test.

Health note: This article is general information about how A1C and prediabetes are defined and screened for — it is not medical advice, and a screening result is not a diagnosis. A1C can read inaccurately in some situations, including certain anemias and blood conditions, and a diabetes diagnosis normally requires confirmatory testing. If you are concerned about your blood sugar, talk to your doctor.

Image: AI-generated illustration.

Sources