Study: Incidence of childhood obesity on the rise, occurs at younger ages

Childhood obesity incidence was higher and came at younger ages during the 2000s compared with the previous decade, according to a study in Pediatrics.

“Obesity in early life remains a leading public health challenge because it is linked with long-term poor physical and mental health,” researchers wrote. “The prevalence of childhood obesity in the United States is among the highest in the world. Although some data suggested that increases in the prevalence of obesity among primary school children had stalled in the early 2000s, recent studies report that the prevalence of obesity among children and adolescents has continued to increase.”

The researchers examined two cohorts of the Early Childhood Longitudinal Study (ECLS), which enrolled children in kindergarten and followed them through fifth grade. The first cohort was followed from 1998 to 2004 and the second from 2010 to 2016, with the ECLS results showing an increase in the incidence of obesity in the 2010 cohort compared with the 1998 cohort.

Further, the researchers found that 72.9% of children entering kindergarten in 1998 had normal BMI, whereas 15.1% had overweight and 12% had obesity. Twelve years later, the percentage of children starting school with a normal BMI had decreased to 69%.

Moreover, among children who entered kindergarten without obesity, 29% more non-Hispanic Black children developed obesity by fifth grade in the later cohort compared with the earlier one. Obesity incidence remained unchanged or decreased in other race and ethnicity groups, results showed.

The authors called for more research and policies aimed at obesity in preschool children.

“We speculate that prevention programs need to look beyond simple solutions to obesity, including addressing the substantial changes in physical activity and in food environments that have progressed in recent decades, as well as the epigenetic and neuro-psycho-behavioral pathways to obesity,” they wrote. “There are no national longitudinal studies of health for today’s children; such data will be necessary to map the changing incidence of obesity across age, gender, social and economic factors, and geographies.”

In an accompanying editorial, Cynthia L. Ogden, PhD, and colleagues from the CDC focused on the racial disparities shown in the results of the study.

“Race and ethnic patterns in obesity prevalence from birth throughout childhood reveal that by the time children enroll in kindergarten, an important period for starting interventions in Hispanic children has already passed,” they wrote. “This finding supports the [AAP’s] recommendation of a life-course approach to identify children ‘early on the path to obesity‘ for primary prevention of obesity. Race and ethnicity-specific trends in obesity prevalence across childhood and adolescence provide additional context for identifying individuals and communities at highest risk of developing obesity.”

Reference:

Ogden C, et al. Pediatrics. 2022;doi:10.1042/peds.2022-056547.