Nearly one in five US youths aged 2 to 19 years had obesity in 2024, with rates climbing sharply through adolescence and severe obesity affecting nearly one in 10 adolescents and young adults, according to a cross-sectional study using electronic health record data from a national research network.
In the study, investigators analyzed body mass index (BMI) measurements from 6.1 million youths across the US who had recorded height and weight measurements within 14 days of each other during 2024. The data came from the National Patient-Centered Clinical Research Network (PCORnet), which queried eight clinical research networks using a common data model. Overall, 19.8% of youths aged 2 to 19 years had obesity, defined as a BMI at or above the 95th percentile for age and sex based on CDC growth standards.
The prevalence of overweight or obesity increased substantially with age. Among participants aged 2 to 5 years, 26.9% had overweight or obesity. This rose to 38.5% among participants aged 12 to 19 years. Severe obesity—defined as a BMI at or above 120% of the 95th percentile—affected 9.2% of this older age group.
Marked disparities emerged across racial and ethnic groups. Among youths aged 12 to 19 years, just 49.5% of American Indian or Alaska Native, 52.3% of Black, 49.1% of Hispanic, and 47.3% of Native Hawaiian or Other Pacific Islander youths had a healthy weight compared with 59.3% of White youths. Severe obesity prevalence in this age group ranged from 3.5% among Asian youths to 15.1% among Native Hawaiian or Other Pacific Islander youths and 13.6% among Black youths.
The investigators used WHO standards for infants younger than 2 years and CDC standards for older children. For the youngest age group, between 3.8% and 9.1% had a BMI at or above the 99th percentile, depending on the racial and ethnic subgroup. Sex-based differences were modest across most age categories.
PCORnet's methodology removed implausible height and weight values but didn't impute missing values. The data source enabled analysis of previously underrepresented groups, including Asian and American Indian or Alaska Native youths, but was limited by incomplete BMI measurements and reliance on electronic health records rather than population-based sampling.
The investigators noted that the overall obesity prevalence aligned with 2025 data from the National Health and Nutrition Examination Survey, suggesting PCORnet may serve as a valid data source for future youth obesity surveillance. The Vanderbilt University Medical Center Institutional Review Board classified the study as non-human participant research.
"These results demonstrate the uneven distribution of obesity and severe obesity across youths in the [United States] and underscore the need for ongoing treatment, prevention, and public health interventions to reduce excess adiposity in youths," wrote lead study author William J. Heerman, MD, of the Department of Pediatrics at the Vanderbilt University Medical Center, and colleagues.
Disclosures can be found in the research letter.
Source: JAMA Network Open
