Prediabetes

Quick definition. Prediabetes is the stage where blood sugar is elevated but not yet high enough to be diabetes. It is a warning sign — and, importantly, often reversible.

What Prediabetes Means

Prediabetes is a metabolic state in which blood glucose levels sit above the normal range but below the cutoff for type 2 diabetes. It signals that the body's glucose regulation is already strained, usually by underlying insulin resistance, even though full diabetes has not developed. The condition is extremely common: the CDC estimates that roughly one in three US adults has prediabetes, and the large majority do not know it because it typically causes no symptoms.

The Diagnostic Cutoffs

Prediabetes can be identified by any of three blood tests, each with its own range that sits between normal and diabetic values:

• A1C: 5.7% to 6.4% (normal is below 5.7%; diabetes is 6.5% or higher)
• Fasting plasma glucose: 100 to 125 mg/dL, known as impaired fasting glucose (normal is below 100)
• Two-hour glucose tolerance test: 140 to 199 mg/dL, known as impaired glucose tolerance (normal is below 140)

Because these tests can capture slightly different aspects of glucose metabolism, a person may meet the threshold on one but not another.

Why It Matters

Prediabetes is significant for two reasons. First, it is a strong predictor of future type 2 diabetes — without intervention, a meaningful share of people with prediabetes progress to diabetes within several years. Second, the elevated glucose and the insulin resistance that drives it begin contributing to cardiovascular risk even before diabetes is diagnosed. Far from being a benign "pre" condition, it represents a window in which the trajectory toward diabetes can still be changed.

How GLP-1 Medications Fit In

GLP-1 receptor agonists are not specifically FDA-approved to treat prediabetes as a standalone diagnosis. However, many people with prediabetes also meet the BMI criteria for a weight-management indication, and the weight loss these drugs produce directly targets the insulin resistance underlying prediabetes. In the obesity trials of high-dose semaglutide and tirzepatide, a substantial proportion of participants who started with prediabetes saw their blood sugar return to the normal range over the course of treatment. The benefit, again, flows largely from weight loss rather than from any prediabetes-specific drug action.

Reversing Prediabetes

The landmark Diabetes Prevention Program showed that intensive lifestyle change — modest weight loss of about 7% of body weight plus regular physical activity — reduced progression to type 2 diabetes by 58%, outperforming metformin. This remains the foundation of prediabetes care: weight management, dietary change, and exercise. For people who also carry excess weight and qualify for treatment, weight-loss medications can amplify those efforts. The central message is hopeful: prediabetes is frequently reversible, and acting during this stage is one of the most effective ways to prevent diabetes altogether.