About 15.8% of American adults have diabetes, which translates to roughly 40.1 million people, or 1 in every 8. That figure includes both people who have been diagnosed and those who don’t yet know they have the condition. An additional 115.2 million adults, more than 2 in 5, have prediabetes, meaning their blood sugar is elevated but hasn’t crossed the diabetes threshold.
Diagnosed vs. Undiagnosed Cases
Of that 15.8% total, 11.3% of U.S. adults have received a formal diagnosis. The remaining 4.5% are living with diabetes but haven’t been told by a doctor. That means more than 1 in 4 adults with diabetes don’t know they have it. These figures come from national health survey data collected between August 2021 and August 2023.
Undiagnosed diabetes is a significant concern because the condition damages blood vessels, nerves, kidneys, and eyes over time, even without symptoms. Many people discover they have diabetes only after developing a complication like vision changes, slow-healing wounds, or kidney problems. A simple blood test during a routine checkup can detect it years before those complications appear.
How Rates Differ by Age
Diabetes prevalence climbs sharply with age. Among adults 18 to 34, only 1.3% have a diagnosis. By age 65 and older, that number jumps to 20.1%, meaning roughly 1 in 5 seniors is living with diagnosed diabetes. This pattern reflects the way type 2 diabetes develops gradually over years as the body becomes less efficient at managing blood sugar, compounded by age-related changes in metabolism and physical activity.
Prediabetes follows the same trajectory. Among Americans 65 and older, an estimated 31.3 million people (52.1%) have prediabetes. In other words, more than half of all seniors have blood sugar levels that are already abnormally elevated.
Type 1 vs. Type 2
The vast majority of diabetes cases in the U.S. are type 2, which develops when the body stops responding effectively to insulin. Roughly 90 to 95% of all diabetes falls into this category. Type 1 diabetes, where the immune system destroys the cells that produce insulin, accounts for the remaining 5 to 10% and is typically diagnosed in childhood or young adulthood, though it can appear at any age.
Among young people under 20, current estimates put type 1 cases at around 191,000. But diabetes in children and teens is increasing. If current trends in new diagnoses continue to accelerate, researchers project type 2 diabetes cases in young people could increase by roughly 700% by 2060, and type 1 cases could rise by about 65%. Even under a more conservative scenario where diagnosis rates hold steady, type 2 cases in young people would still climb by around 70%.
Where Diabetes Rates Are Highest and Lowest
Diabetes prevalence varies dramatically across the country. In 2023, the states with the highest age-adjusted rates of diagnosed diabetes were:
- West Virginia: 15.0%
- Mississippi: 14.7%
- Louisiana: 14.5%
Puerto Rico and Guam both reported rates of 16.0%, the highest among all U.S. states and territories.
At the other end, states in the Mountain West and northern New England reported the lowest rates:
- Vermont: 7.7%
- Montana: 7.9%
- New Hampshire: 7.9%
- Colorado: 8.0%
- Utah: 8.0%
These geographic differences reflect a mix of factors including obesity rates, poverty levels, access to healthcare, diet patterns, and the age and racial composition of each state’s population. The gap between the highest and lowest states is nearly double, highlighting how unevenly diabetes affects different parts of the country.
The Economic Cost
Diabetes costs the U.S. an estimated $413 billion per year when combining healthcare spending and lost economic productivity. Direct medical costs account for $307 billion of that total, a figure that grew by $80 billion over the decade from 2012 to 2022. The remaining $106.3 billion comes from indirect costs: reduced productivity at work ($35.8 billion), missed workdays ($5.4 billion), chronic disability, and premature death.
People with diabetes spend roughly 2.6 times more on healthcare than people of the same age without the condition. Much of that spending goes toward managing complications like heart disease, kidney failure, and nerve damage rather than the diabetes itself. The financial burden falls on individuals, employers, and public insurance programs alike, making diabetes one of the most expensive chronic conditions in the country.