Prevalence of Preclinical and Clinical Obesity Among US Children and Adolescents Aged 5 to 18 Years: NHANES 2017–2023

OBJECTIVE: This study aimed to estimate the prevalence of preclinical and clinical obesity among US youth using the Lancet Diabetes & Endocrinology Commission's framework. METHODS: This cross-sectional study examined NHANES 2017-2023 data from 5513 youth aged 5-18. Obesity classification included: (i) no obesity (BMI < 95th percentile and/or waist to height ratio (WHtR) < 0.5), (ii) preclinical obesity (BMI ≥ 95th percentile and WHtR ≥ 0.5 without clinical impairment or functional limitations), and (iii) clinical obesity (BMI ≥ 95th percentile and WHtR ≥ 0.5 with one or more clinical impairments or functional limitations). RESULTS: The weighted prevalence was 8.3% for preclinical and 12.5% for clinical obesity; combined prevalence (20.8%) was similar to ~22% using BMI percentile alone. Clinical obesity was more common in older children and racial/ethnic minority groups but similar by sex. Impairments associated with clinical obesity included low HDL cholesterol (60.3%), asthma (24.8%), early menarche in girls (18.0%), elevated blood pressure (16.2%), prediabetes/diabetes (9.1%), and functional limitations related to walking (7.7%) and self-care (4.1%). CONCLUSIONS: Applying the Lancet Diabetes & Endocrinology Commission's new definition criteria revealed substantial physiological dysfunction in US youth. Applying preclinical and clinical obesity definitions is challenging, given the limitations of the routinely collected clinical and epidemiological data that make up NHANES and in standard clinical practice.