Roughly 7 in 10 American adults carry excess weight. About 40.3% of U.S. adults have obesity (a BMI of 30 or higher), and an additional portion falls into the “overweight” category (BMI 25 to 29.9), bringing the combined total to approximately 70% of the adult population. Among children and adolescents ages 2 to 19, about 15.1% are overweight and another 21.1% have obesity, meaning more than a third of young Americans are above a healthy weight range.
How Overweight and Obesity Are Defined
These statistics rely on body mass index, a ratio of weight to height. For adults 20 and older, the CDC uses these BMI categories:
- Overweight: BMI of 25 to less than 30
- Class 1 obesity: BMI of 30 to less than 35
- Class 2 obesity: BMI of 35 to less than 40
- Class 3 (severe) obesity: BMI of 40 or greater
For children and teens, the thresholds are different. Overweight means a BMI at or above the 85th percentile for their age and sex, while obesity starts at the 95th percentile. Severe obesity in children is defined as a BMI at or above 120% of the 95th percentile.
Adult Obesity by the Numbers
The most recent national survey data, collected between August 2021 and August 2023, puts adult obesity at 40.3%. Within that group, 9.4% of adults have severe obesity. These figures come from measured heights and weights rather than self-reported data, which tends to undercount the true numbers.
The combined overweight-and-obese figure (everyone with a BMI of 25 or above) has hovered near 70% in recent survey cycles. That means adults at a “normal” weight are now a minority of the U.S. population.
Children and Adolescents
Among Americans ages 2 to 19, 21.1% have obesity and 7.0% have severe obesity, based on the same 2021–2023 survey period. Another 15.1% are overweight but below the obesity threshold. Altogether, more than 36% of U.S. kids and teens are above a healthy weight for their age.
Differences by Race, Sex, and Ethnicity
Obesity rates vary substantially across demographic groups. Black adults have the highest prevalence at 49.6%, followed by Hispanic adults at 44.8% and white adults at 42.2%. Asian American adults have the lowest rate at 17.4%. These gaps are especially pronounced among women: 56.9% of Black women have obesity compared with 43.7% of Hispanic women, 39.8% of white women, and 17.2% of Asian women. Among men, the differences between white, Black, and Hispanic groups are smaller and not statistically significant.
Where Rates Are Highest and Lowest
Geography plays a role too. As of 2024, every U.S. state has an adult obesity rate of at least 25%. The Midwest (35.9%) and South (34.5%) carry the highest regional averages, while the Northeast (30.3%) and West (30.2%) are somewhat lower. Mississippi and West Virginia are the only two states where obesity prevalence hits 40% or higher. Eight states and the District of Columbia remain between 25% and 30%.
How Fast Rates Have Climbed
The speed of this increase is striking. In the early 1960s, 13.4% of American adults had obesity. By the late 1980s and early 1990s, that number had risen to 22.9%. Today it sits at 40.3%, a threefold increase in roughly 60 years. Severe obesity has followed the same trajectory, climbing from a rarity to 9.4% of adults.
Projections from researchers at Harvard suggest the trend isn’t slowing down. Modeling published in the New England Journal of Medicine estimated that about half of U.S. adults will have obesity by 2030, with roughly a quarter reaching severe obesity. The study projected that in 29 states, more than half the population would be affected.
The Financial Cost
Excess weight drives enormous healthcare spending. A systematic review published in the Journal of Managed Care & Specialty Pharmacy found that nationwide medical costs tied to obesity and its complications exceeded $261 billion in 2016 alone. Those costs cover everything from diabetes and heart disease management to joint replacements and sleep disorder treatments. Because the obesity rate has continued climbing since 2016, current spending is almost certainly higher.
Why BMI Doesn’t Tell the Whole Story
All of these statistics depend on BMI, which has real limitations. BMI doesn’t distinguish between fat and muscle, so a muscular person can be classified as overweight despite having low body fat. It also doesn’t account for where fat is stored. Fat around the organs in the midsection (visceral fat) poses greater health risks than fat carried in the hips or thighs, but BMI treats them the same.
The American Medical Association adopted a policy in 2023 recognizing BMI as “an imperfect clinical measure.” The organization noted that BMI loses predictive value when applied to individuals rather than populations, and that body composition varies meaningfully across ethnicities, sexes, and age groups. The AMA now recommends using BMI alongside other measures like waist circumference, body composition, and metabolic markers rather than relying on it alone.
None of this means the population-level trends are wrong. When 4 in 10 adults meet the obesity threshold by any measure, the public health signal is clear. But for any single person, BMI is a rough screening tool, not a diagnosis.