What prediabetes means
Prediabetes means blood sugar results that are higher than the normal range, but not high enough to fall in the diabetes range — that's the definition used by the American Diabetes Association and the CDC. It's a label for where lab results sit between two published thresholds, nothing more mysterious than that.
If a doctor has said this word to you, or a family member just brought it home from an appointment, this page explains the vocabulary in plain English. It doesn't interpret anyone's results — that's your doctor's job — but it should make the next conversation with them clearer.
The numbers behind the word
Prediabetes isn't a feeling or a judgment; it's a range on three specific tests:
| Test | Prediabetes range |
|---|---|
| A1C | 5.7% – 6.4% |
| Fasting glucose | 100 – 125 mg/dL (called "impaired fasting glucose") |
| 2-hour OGTT | 140 – 199 mg/dL (called "impaired glucose tolerance") |
Source: American Diabetes Association, Standards of Care in Diabetes, Section 2. For all three ranges side by side, see the full guide to blood sugar numbers.
How common it is
Far more common than most people guess. The CDC's National Diabetes Statistics Report estimates that 97.6 million US adults aged 18 and over had prediabetes in 2021. And the number that really stops people: more than 8 in 10 adults with prediabetes don't know they have it, according to the CDC.
Prediabetes vs diabetes — the difference in plain English
They're neighboring ranges in the same published tables, not the same thing. Using A1C as the example: 5.7–6.4% falls in the prediabetes range, while 6.5% or higher falls in the diabetes range. The difference is where a result lands against thresholds that health authorities have drawn — and which side of a threshold any individual result lands on, and what that means for that person, is a determination only a clinician can make (the ADA's standards generally require a second confirmatory test before any diagnosis).
Why it often goes unnoticed
Because for many people there's nothing to notice. Prediabetes is defined by lab values, not by how you feel — plenty of people feel completely fine while their results sit in that range. That's the plain reason behind the CDC's "8 in 10 don't know" figure: without a blood test, there's often no signal at all. It's also why the word tends to arrive as a surprise at a routine check-up.
What people usually do next
Most people start with two things: they talk to their doctor about what the result means for them and when to retest, and they take an honest look at their everyday routine — food patterns, movement, sleep. The first part belongs entirely to your healthcare team. The second part — understanding your routine and building daily habits — is the lane this site lives in:
- The free ebook — making sense of your numbers in plain English.
- The Normal Range System — the full 32-page playbook, for when you want the whole approach in one place.
- How to build a daily walking habit that actually sticks — the simplest habit most people start with.
- Glucose spikes explained — another term you'll hear a lot, made plain.
Common questions
What A1C is prediabetes?
In the American Diabetes Association's published ranges, an A1C of 5.7% to 6.4% falls in the prediabetes range. Below 5.7% is described as normal, and 6.5% or higher as the diabetes range. Only a clinician can interpret what your own result means, and a diagnosis generally requires a confirmatory second test.
Does prediabetes mean I'll get diabetes?
No test result can predict any one person's future. Prediabetes is a risk category that health authorities track — it means results sit above the normal range, not that a particular outcome is certain. What it means for your own trajectory, and what to do about it, is exactly the conversation to have with your doctor.
How common is prediabetes?
Very. The CDC's National Diabetes Statistics Report estimates that 97.6 million US adults aged 18 and over had prediabetes in 2021 — and that more than 8 in 10 of them don't know they have it, because it's defined by lab tests rather than by how you feel day to day.