Nov 05, 2016 12:39 AM EDT By Julio Cachila, UniversityHerald Reporter

Children gain weight faster during the school break as compared to when they're in school, according to a new report published in the journal Obesity.

Researchers looked into weight gains and falls of 18,170 U.S. school children who started kindergarten in 2010 to the end of second grade in 2013, measuring their respective weights during fall and spring. They found that during the two summer breaks, obesity prevalence among the kids increased from 8.9% to 11.5%, and overweight prevalence also increased from 23.3% to 28.7%.

The researchers also found that the kids did not gain weight while in school. Instead, they found that obesity prevalence slightly lowered during the school year.

"Educators have long worried that summer break leads to knowledge loss, and now we know that it is also a time of excessive weight gain for our youngest school children," lead researcher Paul von Hippel of the LBJ School of Public Affairs at the University of Texas, Austin, said in a press release.

The findings of the study seem to suggest that the factors raising the risk for child obesity aren't found in schools. Rather, schools prevent overweight and obesity prevalence from increasing, and might reduce the risk for the conditions.

The researchers also noted that it is likely that there are other factors that affect obesity prevalence outside of school but within the school year. They say some of these factors might exist right after class or on the weekends, but with their collected data the researchers are unable to estimate weight gains or losses.

Still, the findings raise up concerns regarding how parents and other authorities could help counter obesity among the children. The researchers note that school-based interventions had little effect, and that effective measures involve not only the schools but also the parents.

"Our findings raise questions for parents and policymakers about how to help children adopt healthy behaviors during the long summer vacation to stop unhealthy weight gain," Hippel said.

Amanda Staiano, PhD spokesperson for The Obesity Society, said they are hoping that the study's findings would urge parents and other authorities to make sure that the summer break would not set back efforts made to fight against obesity during the school year.

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