Prediabetes means blood glucose is higher than normal but not yet high enough to be classified as type 2 diabetes. The American Diabetes Association defines it as an A1c of 5.7–6.4%, a fasting plasma glucose of 100–125 mg/dL (impaired fasting glucose), or a 2-hour oral glucose tolerance test of 140–199 mg/dL (impaired glucose tolerance). It is common, often has no symptoms, and is frequently modifiable with lifestyle change.

Pillar guide · prediabetes

Prediabetes: The Complete Guide

Q: Can prediabetes be reversed?

For many people, glucose can return to the normal range through changes such as diet, physical activity, and weight loss, and structured lifestyle programs have been shown to reduce progression to type 2 diabetes. Whether this counts as reversed or managed varies by person, and results are individual. Any plan should be made with a qualified clinician.

11 min read · Updated July 2026

Prediabetes is the stage where blood glucose is higher than normal but not yet in the diabetes range. It is common, usually silent, and for many people modifiable. This guide explains what prediabetes is, how it's diagnosed, the numbers that define it, what raises your risk, and what the evidence says about turning it around. It's educational, not medical advice.

What prediabetes is

Prediabetes means the body has started to struggle with keeping glucose in a normal range, but the numbers haven't reached the threshold for type 2 diabetes. It sits on the broader spectrum of dysglycemia — abnormal glucose regulation that often appears years before diabetes. Crucially, it is a stage, not a fixed destiny: for many people, it's an early warning that responds to change. Start with What is prediabetes? for the plain-language overview.

The numbers that define it

The American Diabetes Association defines prediabetes three ways, using any one of these test results:

A1c 5.7–6.4% — a blood test reflecting average glucose over ~2–3 months. See the prediabetes A1c range.
Fasting plasma glucose 100–125 mg/dL — known as impaired fasting glucose (IFG).
2-hour oral glucose tolerance test 140–199 mg/dL — known as impaired glucose tolerance (IGT).

Below these ranges is considered normal; at or above A1c 6.5%, fasting 126 mg/dL, or a 2-hour value of 200 mg/dL is the diabetes range. Because a person can meet one criterion but not another, how prediabetes is confirmed matters — see how prediabetes is diagnosed. You can convert an A1c to an estimated average glucose with our HbA1c calculator.

Why it's often silent

Most people with prediabetes have no symptoms at all, which is exactly why it's so often missed and why screening matters. When signs do appear, they tend to be subtle and non-specific. We cover this — and when to seek testing — in prediabetes symptoms (and why there often aren't any).

What raises your risk

Several factors increase the likelihood of prediabetes, including age, excess weight, family history, physical inactivity, a history of gestational diabetes, and certain ethnic backgrounds. Understanding your own risk is the first step toward acting on it — see prediabetes risk factors.

Can it be turned around?

This is the most important — and most hopeful — question. For many people, glucose can move back toward the normal range through changes in eating, activity, and weight, and structured programs like the National Diabetes Prevention Program have been shown to reduce progression to type 2 diabetes. The nuance between "reversed" and "well-managed," and what the evidence actually supports, is covered in can prediabetes be reversed?

Eating patternsEvidence-informed diet for prediabetes ExerciseHow activity improves insulin sensitivity Can it be reversed?What the evidence does and doesn't support CGM for prediabetesWhat a glucose sensor can and can't show

See your glucose patterns early

Prediabetes is easiest to act on when you can see it. Endobits reads the shape of glucose data as clinical decision support under your clinician's oversight.

Check your glucose

The full prediabetes library

What is prediabetes? Prediabetes symptoms How it's diagnosed The A1c range Risk factors Can it be reversed? Eating patterns Exercise Impaired fasting glucose Impaired glucose tolerance CGM for prediabetes What is dysglycemia?

Educational only, not medical advice. Prediabetes is diagnosed by a clinician using standardized blood tests, and any plan for diet, activity, or medication should be made with a qualified healthcare provider. Endobits is clinical decision-support software, not a diagnostic device.

Sources

American Diabetes Association — Diagnosis & diagnostic criteria.
Centers for Disease Control and Prevention — Prediabetes — Your Chance to Prevent Type 2 Diabetes.
NIH / NIDDK — Prediabetes & Insulin Resistance.

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