From 2009 to 2013, the city introduced water dispensers into about 40 percent of their schools. They are large, clear, electronically powered jugs with a push lever for dispensing water. Each water dispenser costs around $1,000.
Researchers at NYU Langone Medical Center wanted to know whether the water dispensers were effective. Their analysis included over one million students in 1,227 elementary and middle schools. They compared students in schools with and without water dispensers.
The researchers found that adding self-serve water dispensers in cafeterias lead to a statistically significant decline in the students' weight.
The study took place over the course of four academic school years (2008-2009 to 2012-2013).
“This [finding] demonstrates that doing something as simple as providing free and [easily] available water to students may have positive impacts on their overall health, particularly weight management,” said senior study investigator Brian Elbel, associate professor of population health and health policy at NYU School of Medicine.
The investigators used annually-collected height and weight data to evaluate student fitness levels. They compared the BMIs and overweight status of all students before and after the introduction of water dispensers.
Water consumption increased by about 300 percent within three months of the schools using water dispensers. During this period, water dispenser schools saw a BMI decline of 0.25 for boys and .022 for girls, compared to non-water dispenser schools. Schools with water dispensers also experienced a .9 percentage point decline in the likelihood of boys being overweight and a .6 percentage point decline in the likelihood of girls being overweight.
Throughout the course of the study, milk purchases dropped at schools with water jets by 12 half-pint cartons per student. “Decreasing the amount of caloric beverages consumed and simultaneously increasing water consumption is important to promote children’s health and decrease the prevalence of childhood obesity,” said Amy Ellen Schwartz, Director of the NYU Institute for Education and Social Policy, and Daniel Patrick Moynihan, Chair in Public Affairs at Syracuse University’s Maxwell School of Citizenship and Public Affairs.
New York City public schools banned selling sugar-sweetened beverages before the study period, but students can bring their own sugary drinks from home. The study shows that easy access to water during lunch lead many kids to substitute caloric beverages with water.
The findings were published on January 19 in the online issue of JAMA Pediatrics.
Sources: NYU Langone Medical Center press release via Newswise