Students may not like them, but strict junk food laws in schools appear to help curb childhood obesity, a new study shows.
The study, published Monday in the journal Pediatrics, found a strong association between children's weight and tough state laws curbing the sales of snacks and sugary drinks, known as competitive food, outside school breakfast and lunch, The New York Times reported.
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Children in the study gained less weight in the fifth through eighth grades if they lived in states with strong "competitive food laws."
Also, children who were overweight or obese in fifth grade were more likely to be at a healthier weight in eighth grade if they lived in states with the strongest such laws, according to The Associated Press.
The results weren't huge and the study wasn't conclusive, but it raised optimism among public health experts and obesity researchers about the promise of laws that curb junk food in schools.
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"We have found that kids eat less junk food when there is less junk food in schools," Dr. Marlene Schwartz, deputy director of the Rudd Center for Food Policy and Obesity at Yale University, told US News & World Report. "This is the first big national study that looked at the laws."
Child obesity has tripled over the past three decades, according to the US Centers for Disease Control and Prevention.
In 2008, 20 percent of children aged 6 to 11 were considered obese.