What the study found: One million children developed obesity during the pandemic
Experts have worried how lifestyle disruptions caused by the COVID pandemic affected pediatric obesity rates. New research shows a small but meaningful jump.
Pediatric obesity rose by 1.4% during the pandemic – an increase of 1 million young people in just a few years.
Researchers at Children’s HealthSM and UT Southwestern made this discovery based on data from National Health and Nutrition Examination Surveys (NHANES) conducted in 2017-2020 (pre-pandemic) and 2021-2023 (during the pandemic).
New NHANES analysis highlights rising pediatric obesity and need for multifaceted treatment
The research also marks one of the first times that NHANES dietary data was codified using the Nova classification system for processed foods.
The findings: More than 60% of an American child’s calories came from ultra-processed foods (UPFs).
The researchers say their findings confirm the multifactorial causes of obesity and the need for both macro and micro solutions.
“On a national level, policymakers need to align food label reform, dietary guidelines and school food offerings. At the patient level, providers must understand and address the complex web of factors that influence a child’s food and activity habits,” says Bethany Cartwright, M.D., Pediatric Endocrinologist at Children’s Health and Assistant Professor at UT Southwestern.
NHANES provides a reliable population-level view
The study compared data from 4,756 children and adolescents who participated in the examination and survey before the pandemic and 2,501 who participated during it. The surveys included BMI data and self-reported accounts of physical activity and daily diet.
“The NHANES sampling frame is complex, the data is cleaned – it’s as reliable and representative as a large survey like this can be,” says Sarah Messiah, Ph.D., Professor of Epidemiology in the O’Donnell School of Public Health and Director of the Child and Adolescent Population Health Program at UT Southwestern.
The comparison showed overall obesity rose from 21.2% to 22.6%. Within that rise, each class of obesity saw a small increase as well.
“More children experienced obesity during the pandemic, and many children who were already living with the condition saw their condition progress,” says Dr. Messiah.
UPF consumption went down but is still alarmingly high
Investigators used the Nova classification system to categorize respondents’ food intake based on the extent, nature and purpose of processing of each food item.
They found that American youth received 66% of their calories from UPFs before the pandemic, compared with 62.7% during the pandemic.
Why did UPF consumption decrease during a period that saw obesity increase? The answer may lie in the variability among individual patients and families.
“Population-level data gives an invaluable overview, but it hides the heterogeneity that exists on the patient level,” says Dr. Cartwright. “Clinicians who treat obesity every day know that some families had the resources to eat more home cooking during the pandemic, while some were just in survival mode and relied on UPFs even more than before.”
Regardless of the decrease, UPFs are still far too prevalent. And that prevalence stacks the odds against kids and families.
“Obesity isn't always a matter of people not trying hard enough to make healthy food choices,” says Sarah Barlow, M.D., Pediatric Gastroenterologist at Children’s Health and Professor at UT Southwestern. “There's a lot in their environment that families can't do anything about.”
Physical activity emerged as the only protective factor
The study validated the power of daily physical activity (PA) to prevent obesity. Both before and during the pandemic, children who got 60 minutes of daily activity were less likely to experience obesity than those who were less active.
The investigators note that PA has health benefits in all cases – but it’s more effective at preventing weight gain than promoting weight loss.
“Many families are surprised to learn this,” says Dr. Cartwright. “They think a child should be able to lose weight with lifestyle changes alone. But as obesity increases, the body has many physiological processes that work against weight loss.”
Patients need personalized care
The variability of PA, UPF consumption and other factors at the individual level underlines the need for providers to discern the unique barriers and circumstances of each patient so they can recommend the best interventions. And while the pandemic was a major environmental stressor affecting everyone at once, many families experience something akin to that on a daily basis.
“Economic pressure and traumatic personal pressures can directly affect a family’s lifestyle and health,” says Dr. Cartwright. “That's another reason it's important for the clinician to find out what's going on with the family and help with those difficulties however they can.”
Learn more about the COACH Program for childhood obesity at Children’s Health.
