Prevalence of Obesity and Severe Obesity in US Children, 1999-2016

To provide updated prevalence data on obesity trends among US children and adolescents aged 2 to 19 years from a nationally representative sample. We used the NHANES for years 1999 to 2016. Weight status was determined by using measured height and weight from the physical examination component of the NHANES to calculate age- and sex-specific BMI. We report the prevalence estimates of overweight and obesity (class I, class II, and class III) by 2-year NHANES cycles and compared cycles by using adjusted Wald tests and linear trends by using ordinary least squares regression. White and Asian American children have significantly lower rates of obesity than African American children, Hispanic children, or children of other races. We report a positive linear trend for all definitions of overweight and obesity among children 2-19 years old, most prominently among adolescents. Children aged 2 to 5 years showed a sharp increase in obesity prevalence from 2015 to 2016 compared with the previous cycle. Despite previous reports that obesity in children and adolescents has remained stable or decreased in recent years, we found no evidence of a decline in obesity prevalence at any age. In contrast, we report a significant increase in severe obesity among children aged 2 to 5 years since the 2013-2014 cycle, a trend that continued upward for many subgroups.