What Percentage of Americans Have Diabetes or Prediabetes?

Roughly 10 percent of Americans live with diagnosed diabetes, according to recent federal estimates.5%, or about 38.4 million people across the United States, based on figures from the Centers for Disease Control and Prevention (CDC). Add the 88 million adults in the prediabetes range, and close to half of all Americans show some form of impaired blood sugar regulation, often without knowing it.

This guide covers the latest CDC statistics on diabetes and prediabetes, breaking down diagnosed versus undiagnosed cases and how the numbers shift across age, ethnicity, and weight groups.

The Scale of Diabetes and Prediabetes Across the U.S.

The latest CDC figures place diagnosed diabetes at about 10.5% of the U.S. population, which translates to roughly 38.4 million Americans. Among that group, an estimated 8.5 million cases remain undiagnosed, meaning blood sugar levels already meet the clinical threshold for diabetes but the person has never been tested or told. That hidden portion matters because untreated high blood sugar quietly damages blood vessels, nerves, and organs for years before symptoms become obvious.

Prediabetes prevalence in America is even higher. An estimated 88 million U.S. adults, or roughly one in three, have blood sugar levels higher than normal but not yet in the diabetes range. The National Diabetes Statistics Report, published periodically by the CDC, frames the combined picture: nearly half of all Americans show some form of impaired glucose regulation.

That translates into a meaningful chance that someone in your close circle, a parent, a sibling, a coworker, is already living with one of these conditions, often without a formal diagnosis.

Both the CDC and the American Diabetes Association (ADA) treat prediabetes as a warning zone rather than a diagnosis, and catching it early gives you a real chance to prevent progression through lifestyle changes alone.

Diagnosed Versus Undiagnosed Cases Explained

Diagnosed diabetes refers to cases confirmed through clinical testing and reported by a healthcare provider, most commonly a fasting plasma glucose test, an A1C blood test, or an oral glucose tolerance test. Once a clinician files that diagnosis, the case enters the public health data. That is the population captured in the 10.5% figure.

Undiagnosed diabetes describes the same clinical reality, blood sugar that meets the diabetes threshold, but without the patient ever being tested or told. The CDC estimates roughly 2.5% of Americans fall into this silent group. They feel fine, but the underlying damage to small blood vessels and nerves has usually already begun. The difference between the two groups comes down to access to screening and the presence of symptoms severe enough to send someone to a clinic.

Routine screening matters because prediabetes and early diabetes develop without obvious warning signs. Fatigue, increased thirst, blurry vision, and frequent urination tend to appear only after glucose has been elevated for some time. The ADA recommends testing for adults 45 and older, and earlier for anyone with risk factors such as a body mass index (BMI) of 25 or higher, a family history of diabetes, or a previous gestational diabetes diagnosis.

Knowing your A1C levels gives you a single number that reflects your average blood sugar over the past two to three months.

Type 1, Type 2, and Gestational Diabetes at a Glance

Those headline statistics mix three distinct conditions under one umbrella, and understanding the differences clarifies who is at risk and why.

Type 2 Diabetes Dominates the Numbers

Roughly 90 to 95 percent of every diagnosed diabetes case in the United States turns out to be type 2. It usually develops in adults over 45, though rates are climbing among younger people, including adolescents, alongside rising obesity. The underlying mechanism is insulin resistance, where muscle, liver, and fat cells stop responding efficiently to insulin. The pancreas then overproduces insulin until it eventually cannot keep up.

Type 1 Diabetes Is Autoimmune and Less Common

Type 1 diabetes represents roughly 5–10% of cases and is typically diagnosed earlier in life, often in childhood or adolescence. It is an autoimmune condition in which the immune system destroys the insulin-producing beta cells of the pancreas. People with type 1 require insulin from the start because their bodies no longer make it.

The condition is not tied to weight or lifestyle in the same way type 2 is, which is why prevention messaging focuses almost entirely on type 2.

Gestational Diabetes Appears During Pregnancy

Gestational diabetes affects an estimated 2–10% of pregnancies annually in the U.S., based on data from the National Institute of Diabetes and Digestive and Kidney Diseases. It typically develops around the 24th week and usually resolves after delivery, though it raises the mother’s lifetime risk of type 2 diabetes substantially. Babies born to mothers with gestational diabetes also face higher risks for early obesity and glucose intolerance later in life.

Those mechanisms help explain why certain groups shoulder a disproportionate share of the disease.

Who Is Most Affected by Age, Ethnicity, and Weight

Diabetes does not strike evenly, and the patterns by age, race, ethnicity, and body weight shape individual risk in ways worth understanding.

Age Drives a Sharp Rise in Prevalence

Prevalence climbs steeply with age. Among adults 65 and older, diagnosed diabetes rates exceed 25%. In younger brackets (18–44), rates hover closer to 3–4%. The gap reflects decades of accumulated weight gain, reduced physical activity, and gradual loss of insulin-producing capacity. Age is one of the strongest predictors of risk, and screening recommendations account for this directly.

Racial and Ethnic Disparities Are Persistent

Higher diabetes rates are consistently reported among Black, Hispanic, American Indian, and Asian American adults compared with non-Hispanic white adults. Black Americans face roughly 1.4 times the risk, Hispanic Americans about 1.7 times, and American Indian adults in some tribal communities reach rates above 14%. These disparities reflect a combination of genetic predisposition, food access, healthcare access, and the cumulative stress of economic disadvantage. Addressing them requires both individual screening and broader public health investment.

Weight, Activity, and Family History Compound Risk

Several individual factors stack the deck against you:

Age, ethnicity, and weight combine to shape who crosses that threshold first.

• ▸Body mass index of 25 or higher. Excess weight, especially around the abdomen, is the strongest modifiable risk factor for type 2 diabetes.
• ▸Physical inactivity. Skipping regular movement reduces how efficiently your muscles use glucose, accelerating insulin resistance.
• ▸Family history. A parent or sibling with type 2 diabetes roughly doubles your own risk.
• ▸Gestational diabetes history. Women who had gestational diabetes face a 40–60% chance of developing type 2 within 10–20 years.
• ▸Polycystic ovary syndrome (PCOS). PCOS frequently coexists with insulin resistance and raises diabetes risk substantially.

Why Prediabetes Often Progresses Without Intervention

Insulin resistance can simmer for years before any standard blood test turns abnormal. That delay is the core reason prediabetes so often slides into diabetes without warning.

The Silent Window of Insulin Resistance

Between 15% and 30% of people with untreated prediabetes develop type 2 diabetes within five years, according to long-term follow-up studies. In the meantime, blood vessel damage and metabolic strain accumulate. The ADA frames prediabetes as a reversible metabolic state, but only if the window is taken seriously.

Modest Lifestyle Changes Cut Progression Risk Dramatically

Research shows that structured programs targeting modest weight loss (5–7% of body weight) and 150 minutes of weekly physical activity can cut progression to diabetes by more than half. The CDC’s National Diabetes Prevention Program is built around exactly this approach. For someone weighing 200 pounds, a 5% loss means dropping 10 pounds, a small target with an outsized payoff. Improvements in diet quality, sleep, and stress management amplify the effect.

Most people who develop type 2 diabetes already lived with prediabetes for years before diagnosis. Catching it in that window gives you a real chance to reverse the trajectory without medication.

That said, awareness alone does not halt the slide into full-blown diabetes.

Practical Steps for Screening, Prevention, and Reversal

Translating statistics into action requires knowing which tests to ask for, how often to repeat them, and what a structured prevention program looks like in practice.

Screening Tests Worth Knowing

Three blood tests dominate diabetes screening:

• ▸Fasting plasma glucose (FPG). Measures blood sugar after at least eight hours without eating. A reading of 100–125 mg/dL signals prediabetes; 126 mg/dL or higher on two occasions signals diabetes.
• ▸A1C test. Reflects average blood sugar over two to three months. A range of 5.7–6.4% signals prediabetes; 6.5% or higher signals diabetes.
• ▸Oral glucose tolerance test (OGTT). Measures blood sugar two hours after a sugary drink. A 140–199 mg/dL reading signals prediabetes; 200 mg/dL or higher signals diabetes.

The CDC recommends testing for adults 45 and older, and earlier for anyone with a BMI of 25 or higher plus an additional risk factor. Retesting every one to three years makes sense if your results are normal but risk factors remain.

Prevention Strategies That Hold Up

Structured lifestyle programs remain the most evidence-based path for reducing diabetes risk. They focus on four core levers:

• ▸Modest, sustained weight loss. Losing 5–7% of body weight improves insulin sensitivity within months.
• ▸Regular physical activity. Aim for 150 minutes per week of moderate activity, such as brisk walking, spread across most days.
• ▸Diet quality upgrades. Emphasize fiber-rich vegetables, whole grains, legumes, and lean proteins while reducing added sugars and refined carbohydrates.
• ▸Consistent sleep and stress management. Poor sleep and chronic stress both elevate cortisol, which raises blood sugar independently of food intake.

The CDC’s National Diabetes Prevention Program offers a year-long structured curriculum through in-person and virtual providers. Many insurance plans, including Medicare, now cover participation. If you are at risk, ask your primary care clinician for a referral or look up local programs through the CDC directory.

Broader Stakes: Costs, Mortality, and Where the Trend Is Headed

The human cost of diabetes extends well beyond individual diagnoses. Diabetes ranks as the seventh leading cause of death in the United States, and the ADA estimates that total annual diabetes-related healthcare expenditures exceed $327 billion when lost productivity is included. That figure covers medications, hospitalizations, complications like kidney failure and lower-limb amputation, and the everyday management that millions of households absorb.

Projections from the CDC and the World Health Organization suggest continued growth in prevalence without expanded prevention, screening, and equitable care access. The most rapid increases are expected among adults under 40 and in communities that already face the highest baseline rates. Two practical things follow from this. First, the trend line is not yet bending. Second, the single most effective intervention still sits in the space between you and your next meal, your next walk, your next lab appointment.

Bottom Line

About one in ten Americans has diabetes, and roughly one in three adults has prediabetes. Most of those cases are type 2, most are tied to weight and activity, and most can be delayed, prevented, or reversed when caught early. Your A1C number, your weight trajectory, and your screening habits are the levers that actually move your personal risk.

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