About 40.1 million people in the United States have diabetes, roughly 1 in every 8 Americans. That makes it one of the most widespread chronic conditions in the country. And the number grows substantially when you factor in prediabetes: an estimated 115.2 million adults, or about 42.6% of the adult population, have blood sugar levels high enough to qualify.
Type 2 Accounts for Most Cases
Not all diabetes is the same. Type 2 diabetes, where the body gradually loses its ability to use insulin effectively, makes up about 90.9% of all diagnosed cases. Type 1 diabetes, an autoimmune condition where the body stops producing insulin entirely, accounts for roughly 5.8%. The remaining fraction includes rarer forms like gestational diabetes and other genetic subtypes.
This distinction matters because the two types have very different causes. Type 1 typically appears in childhood or young adulthood and isn’t preventable. Type 2 develops over years, is strongly linked to weight, physical activity, and diet, and is often preceded by a long period of prediabetes where intervention can still change the trajectory.
Prediabetes Is Even More Common
The 40.1 million figure only captures people who have crossed the diagnostic threshold. Behind them is a much larger group: 115.2 million adults with prediabetes as of 2023. That means their blood sugar is elevated but not yet high enough for a diabetes diagnosis. Without changes to diet, exercise, or body weight, a significant portion of these individuals will develop type 2 diabetes within a decade.
Among adults 65 and older, the numbers are especially striking. An estimated 31.3 million people in that age group have prediabetes, representing 52.1% of all older adults. Age is one of the strongest risk factors for insulin resistance, which is why screening becomes more important as you get older.
Rates Differ Sharply by Race and Ethnicity
Diabetes does not affect all communities equally. The diagnosed rates among U.S. adults from 2021 to 2023 break down like this:
- Black, non-Hispanic: 12.2%
- Hispanic: 11.8%
- Asian, non-Hispanic: 9.7%
- White, non-Hispanic: 7.1%
Black and Hispanic adults are diagnosed at nearly twice the rate of white adults. These gaps reflect a combination of factors: differences in access to healthcare and healthy food, higher rates of obesity in some communities, genetic predisposition, and the cumulative health effects of economic inequality. Asian Americans, while lower in overall rates than Black and Hispanic populations, face elevated risk at lower body weights compared to white adults, which means standard screening guidelines sometimes miss them.
The Financial Weight of Diabetes
Diabetes is the most expensive chronic condition in the United States. Between direct medical costs and lost work productivity, the total economic burden reaches $413 billion a year. People with diabetes spend roughly double what people without the condition spend on healthcare. That includes medications, regular lab work, specialist visits, and, for many, the cost of managing complications like kidney disease, nerve damage, or vision loss that develop over time.
These costs fall unevenly. People without insurance or with high-deductible plans often delay care or ration supplies like insulin and glucose monitors, which accelerates complications and drives costs even higher down the line.
Why the Numbers Keep Growing
Several forces are pushing diabetes prevalence upward. Obesity rates have climbed steadily for decades, and excess body fat, particularly around the abdomen, is the single strongest modifiable risk factor for type 2 diabetes. The American diet has shifted toward processed foods high in added sugars and refined carbohydrates. Physical activity levels remain well below recommended thresholds for most adults. And because the U.S. population is aging, more people are entering the age range where diabetes risk accelerates.
Better screening also plays a role. As more people get tested, more cases that might have gone undetected in previous decades now show up in the data. This is partly a good thing: catching diabetes early gives people more time to manage it before complications set in. But it also means the headline numbers will likely continue rising even if the underlying rate of new cases levels off.
What 1 in 8 Actually Means
When you combine the 40.1 million people with diagnosed diabetes, those who are undiagnosed, and the 115.2 million with prediabetes, the reality is that a majority of American adults have some degree of blood sugar dysfunction. For most, this develops gradually and silently. Type 2 diabetes can go years without obvious symptoms, which is why routine blood sugar checks, particularly after age 35 or earlier if you have risk factors like a family history or a higher body weight, are one of the simplest ways to catch it while the condition is still highly manageable.