Adolescent weight gain during pandemic linked to income and gender in US investigation

16 Aug 2023 --- Investigators at Children’s Hospital Los Angeles (CHLA) in the US have found that excess weight gain in adolescents during COVID-19 was linked to family income. Weight gain was greatest in low-income youth who were already “disproportionately affected” by obesity.

According to the investigation, girls from lower-income families gained the most pandemic-related weight. 

In a research letter published in JAMA Pediatrics, the investigators explained that stress, lack of exercise and poor nutrition resulting from the disruption and isolation of the pandemic shutdown led many children and adolescents to gain excess weight. 

Inside the study
The results were found in children participating in the National Institutes of Health-sponsored Adolescent Brain Cognitive Development (ABCD) study, reportedly the largest long-term study of brain development and child health in the US.

In the ABCD study, a national consortium of researchers has been following over 11,000 children from ages nine or ten until they turn 19 or 20, regularly measuring their height and weight and conducting brain scans and cognitive assessments every other year.

The participants’ family income was also recorded.

“We know from watching the news over the past three years that lower-income families were hit much, much harder by the pandemic than their wealthier counterparts,” says Dr. Elizabeth Sowell, an investigator in CHLA’s Division of Neurology in the Department of Pediatrics and corresponding author on the letter.

“Of those 11,000 kids, we followed about 400 families at CHLA. Most of this sample population is very low-income Hispanic families – which is important because they are typically reticent to enroll in long-term research.”

Pandemic’s hidden impacts 
The CHLA team realized that the ABCD Study could also provide a unique window into the pandemic’s hidden impacts on a large, diverse group of children.

“These kids happened to be recruited between 2016 and 2018 – before the pandemic – and that's important to note,” says Dr. Sowell. “Roughly a third had their second baseline assessment after the pandemic started – so what we had was a natural experiment.”A research team led by Dr. Elizabeth Sowell at the Children's Hospital Los Angeles found disparities in pandemic weight gain in adolescents.

The researchers compared the weight gain of participants whose one-year and two-year follow-up assessments were conducted before March 2020 to the weight gain of another group of participants whose two-year follow-up occurred after the COVID-19 shutdown.

The group of girls assessed during the pandemic gained an average of about 15 pounds per year – 11.2% more than the cohort of girls assessed pre-pandemic, who gained 13.4 pounds per year.

In boys, average weight gain increased by almost 16% between the groups assessed before and during the pandemic.

While the rate of weight gain during the pandemic of girls from wealthier families was similar to before the pandemic, the researchers found that girls from low-income families gained the most weight during the COVID-19 shutdown – they experienced an accelerated average 3.4-pound (24%) weight gain.

Unknown long-term effects
The researchers will track this group of children until the ages of 19 or 20, as ABCD study funding is currently guaranteed through 2027, although they hope the study will continue beyond that point.

The entire study cohort of 11,000 youth is now undergoing their sixth-year assessment, including brain imaging and another set of weight and height measures to calculate body mass index.

“While it’s normal for this age group to grow and gain weight, in this study we will be able to follow these kids over time to see if the excess pandemic weight gain has lasting effects,” says Dr. Sowell.

“We are also evaluating whether the group followed during the pandemic has changes or differences in brain maturation, as well as behaviors like anxiety and depression.”

Yesterday, we explored how packaging designed to appeal to children for food products that contain high or medium amounts of sugar is driving obesity.

Edited by Joshua Poole