The Prevalence of Childhood Obesity Depends on Which Body Composition and Anthropometric Measurement and Cutoff Were Used

Abstract

ABSTRACT Using the 2017–2018 National Health and Nutrition Examination Survey (weighted population size = 35,460,209; 8–18 years old; 52.1% males), we compared the obesity prevalence in children and adolescents between body mass index-based (BMI-based) and total percent body fat-based (BF%-based, measured by the dual-energy x-ray absorptiometry) cutoffs. The BMI-based cutoffs exhibited closer alignments (k, .88–.97) in the childhood obesity prevalence, while the absolute (sex-specific) BF% cutoffs had higher prevalence rates than the relative (age- and sex-specific) BF% cutoffs (k = .43 [95% CI, 0.38–0.49]), overly labeling Non-Hispanic white and Other race/ethnicity females with obesity. The BF%-based cutoffs had higher prevalence rates in most sex, age, and race/ethnicity groups than the BMI-based cutoffs. Furthermore, the absolute BF% cutoffs overly labeled Hispanic and Other race/ethnicity females with obesity. In summary, childhood obesity prevalence varied by sex, age, race/ethnicity across different cutoffs, with the BMI-based cutoffs showing closer alignments than the BF%-based cutoffs.