Prevalence of Clinical Obesity in US Adults, 2017–2020

ABSTRACT Objective We aimed to estimate the prevalence of clinical obesity among US adults using the newly proposed definition and evaluate differences across demographic subgroups. Methods This cross‐sectional study analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2017–2020 cycle. The analysis included 8037 adults aged 20 years or older with complete data. Clinical obesity was defined per the Lancet Diabetes & Endocrinology Commission on the definition and diagnosis of clinical obesity. Results Among 8037 participants, the overall prevalence of clinical obesity was 9.7% (95% CI, 8.9%–10.5%), with comparable prevalence in males (9.8%) and in females (9.6%). Younger adults (aged 20–39 years) exhibited the highest prevalence (11.9%), followed by those aged 40–59 years (8.2%). Significant racial/ethnic and sex disparities were observed, with Mexican females having the highest prevalence (13.9%), followed by non‐Hispanic Black females (13.5%) and non‐Hispanic White males (10.6%). The prevalence decreased significantly when the new definition with organ dysfunctions or limitations of daily activities was applied compared with BMI alone. Conclusions This study provided the first nationally representative estimates of clinical obesity prevalence in US adults based on the new definition.