Obesity Rates Surge to 40% of U.S. Adults and 20% of Youth, New Research Reveals

Obesity rates among U.S. adults and children have risen sharply over the past two decades, reaching 40% of adults and 20% of youth in 2023, according to new independent research published today in the American Heart Association’s flagship journal Circulation. The study, led by Dr. Anum Minhas from the Johns Hopkins School of Medicine, analyzed data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2023, and is believed to be the most contemporary evaluation of obesity trends in the country.

“Obesity is a leading public health concern, linked to higher risks for cardiovascular disease and premature death,” said Minhas. The study found that the prevalence of obesity among adults increased from 30% in 1999 to 41% in 2023. Severe obesity, defined as a body mass index (BMI) of 40 kg/m² or higher, rose from 5% to 10%, and abdominal obesity—excess fat around the abdomen—increased from 48% to 61% over the same period. Among youth, overall obesity increased by about 30%, severe obesity by 50%, and abdominal obesity tripled.

Obesity is a major modifiable risk factor for health conditions including Type 2 diabetes, high blood pressure, heart disease, stroke, and chronic kidney disease. The first-ever guideline from the American Heart Association on cardiovascular-kidney-metabolic syndrome, published in June 2026, highlights obesity as the first stage of the syndrome and emphasizes diet and lifestyle modifications for prevention. The study’s findings underscore the urgent need for individual and population-wide interventions.

The analysis also revealed significant disparities. Women were more likely to have severe obesity (13%) and abdominal obesity (70%) compared to men (7% and 51%, respectively), possibly due to hormonal differences. Non-Hispanic Black individuals consistently had the highest prevalence of obesity across all demographic groups throughout the study period.

“We must increase the availability and use of individual and population-level initiatives to target the rising epidemic of obesity,” Minhas said. She noted that effective weight loss therapies, including GLP-1 receptor agonist medications, bariatric surgery, and other treatments, have been shown to improve metabolic risk factors and cardiovascular health. The study recommends ongoing monitoring of BMI and waist circumference to guide prevention efforts.

The research included nearly 8,700 participants, with about one-third youth under 20 and two-thirds adults 20 and older. Limitations include the use of BMI to define obesity, which does not account for body composition, and declining NHANES response rates over time, which may introduce nonresponse bias. Nevertheless, the findings have major implications for cardiovascular disease and mortality, calling for targeted public health initiatives and better understanding of which patients benefit most from treatments.

For more information, see the full manuscript and the American Heart Association’s guideline on cardiovascular-kidney-metabolic syndrome.