School closures due to the COVID-19 pandemic will exacerbate the epidemic of childhood obesity in the US, according to public health scientists at Columbia University's Mailman School of Public Health.

Researchers expect school closures will double holiday time this year for many children, exacerbating the risk factors for weight gain that are associated with the summer holidays.

Andrew Rundle, associate professor of epidemiology and his colleagues have published their work in Obesity, the journal of the Obesity Society.

Data show children experience unhealthy weight gain during the summer months when they're out of school and that this effect is particularly apparent in children who are already overweight.

"There could be long-term consequences during the COVID-19 pandemic," says Rundle, who specialises in research to prevent childhood obesity.

"Research shows weight gained over the summer months is maintained during the school year and accrues from summer to summer. When a child experiences obesity, even at a young age, they are at risk for higher, unhealthy weight, all the way into middle age."

The authors suggest a number of strategies for reducing the risk, including building physical education into remote teaching plans and offering home lesson plans for physical activity and/or streaming exercise classes.

"The COVID-19 pandemic is responsible for widespread sickness and death, straining healthcare systems, shutting down economies, and closing school districts," says Rundle. "While it's a priority to mitigate its immediate impact, it's also important to consider ways of preventing its long-term effects, including new risks for childhood obesity."