Type 2 diabetes is extremely common and getting more so. Globally, over 800 million adults now live with diabetes, and the vast majority of cases are type 2. In the United States alone, 40.1 million people have diabetes, roughly 1 in every 8 adults. Those numbers have been climbing steadily for decades, and they don’t capture the full picture.
Global Prevalence Has Doubled Since 1990
Worldwide diabetes prevalence in adults rose from 7% to 14% between 1990 and 2022, according to the World Health Organization. That’s a fourfold increase in total cases over roughly three decades, driven largely by rising obesity rates, aging populations, and shifts toward more sedentary lifestyles. By 2045, projections estimate 783 million people aged 20 to 79 will have diabetes, up from about 537 million in 2021.
Type 2 accounts for roughly 90% to 95% of all diabetes cases globally. The remainder includes type 1 diabetes, gestational diabetes, and rarer forms. So when you see a headline about diabetes numbers climbing, it’s overwhelmingly a story about type 2.
U.S. Numbers in Context
The CDC puts the total diabetes prevalence among U.S. adults at 15.8%. That includes both people who know they have it (11.3%) and people who don’t (4.5%). Slightly more than one in four American adults with diabetes are walking around undiagnosed, meaning their blood sugar is high enough to qualify as diabetic but they’ve never been told by a doctor.
On top of that, another 115.2 million U.S. adults have prediabetes, a condition where blood sugar levels are elevated but not yet in the diabetic range. Among adults 65 and older, more than half (52.1%) have prediabetes. Without lifestyle changes, a significant portion of those people will progress to type 2 diabetes within several years.
How Age Affects Your Risk
Type 2 diabetes becomes dramatically more common with age. The condition is most prevalent among adults 65 and older, where both diagnosed diabetes and prediabetes reach their highest rates. Younger adults in their 20s and 30s have much lower rates, though the gap has been narrowing.
One of the more alarming trends is the rise in type 2 diabetes among children and teenagers. In 2002, about 9 per 100,000 young people were newly diagnosed with type 2 each year. By 2018, that number had doubled to 18 per 100,000, a pace of roughly 5% more new cases per year. Type 2 diabetes in young people was once rare enough that the condition used to be called “adult-onset diabetes.” That term was dropped because it no longer fit reality.
Prevalence Varies Sharply by Race and Ethnicity
Type 2 diabetes does not affect all communities equally. CDC data from 2021 to 2023 shows striking differences in diagnosed diabetes rates among U.S. adults:
- American Indian or Alaska Native: 15.7%
- Black, non-Hispanic: 12.2%
- Hispanic: 11.8%
- Asian, non-Hispanic: 9.7%
- White, non-Hispanic: 7.1%
American Indian and Alaska Native adults are more than twice as likely to have a diabetes diagnosis as white adults. These disparities reflect a combination of genetic susceptibility, differences in access to healthcare and healthy food, and the cumulative effects of socioeconomic inequality. They are not simply a matter of individual choices.
Income and Diabetes Are Closely Linked
People living in poverty develop type 2 diabetes at much higher rates. Between 2019 and 2021, 13.1% of U.S. adults with family incomes below the federal poverty level had diabetes, compared to 5.1% of those earning five times the poverty level or more. That’s a nearly threefold difference.
The reasons are layered. Lower-income neighborhoods often have fewer grocery stores stocking fresh produce and more fast-food outlets. Physical activity infrastructure like parks, sidewalks, and gyms tends to be less available. Chronic stress from financial insecurity raises hormones that push blood sugar higher. And people without consistent health insurance are less likely to catch prediabetes early enough to reverse course. The result is that type 2 diabetes concentrates in the communities least equipped to manage it.
Why a Quarter of Cases Go Undiagnosed
Type 2 diabetes often develops gradually over years, and in its early stages it may cause no obvious symptoms. You can have blood sugar levels well above normal without feeling noticeably different. The classic warning signs, like frequent urination, increased thirst, blurred vision, and slow-healing wounds, typically show up after the disease has been present for some time. By that point, elevated blood sugar may have already begun damaging blood vessels, nerves, and organs.
The fact that roughly 26% of U.S. adults with diabetes don’t know they have it underscores how quietly the condition develops. Routine blood work is the most reliable way to catch it. The American Diabetes Association recommends screening for all adults starting at age 35, or earlier if you have risk factors like being overweight, having a family history of diabetes, or belonging to a higher-risk racial or ethnic group.
The Trajectory Is Still Climbing
Every major indicator is moving in the wrong direction. Global cases quadrupled in three decades. Youth diagnoses doubled in sixteen years. The number of American adults with prediabetes now exceeds 115 million. These trends are driven by the same forces: populations are getting heavier, less physically active, and older, while ultra-processed diets have become the global norm.
What makes type 2 diabetes different from many chronic diseases is that it is often preventable or reversible in its early stages. Modest weight loss of 5% to 7% of body weight, combined with regular physical activity, reduces the risk of progressing from prediabetes to diabetes by about 58%. The condition is staggeringly common, but it’s not inevitable.