Attending a financially poor school may have more of an effect on unhealthy adolescent weight than family poverty, according to Penn State sociologists.
Poor schools even influence how parental education protects kids from becoming overweight.
"It was once thought that family income was the main factor when we talk about the research on adolescent weight," said Molly Martin, assistant professor of sociology and demography. "That's not true. The environments the children live in play a key role in weight problems among adolescents."
Martin said that the level of a school's financial resources significantly predicted adolescent weight problems, but the average education level of the parents for students in those schools did not.
The researchers said that students with well-educated parents are less likely to be overweight. However, the effect of having a better-educated parent is minimized if the student attends a poor school, said Michelle Frisco, associate professor of sociology and demography.
A parent with a graduate degree and who has a child in a poor school is more likely to raise an overweight adolescent than a parent with an eighth grade education who has an adolescent enrolled in a rich school, according to researchers.
"The environment can actually limit our ability to make the choices that we all think we make freely," said Frisco.
Many experts believe that well-educated parents can use more tools to help their children maintain a healthy weight, despite environmental pressures, Martin said. For instance, they can recognize health issues associated with being overweight and are more comfortable communicating with doctors. Well-educated parents can also teach their children about nutrition and food choices.
The researchers, who report their findings in the current issue of Social Science and Medicine, analyzed data from the National Longitudinal Study of Adolescent Health that included information about 16,133 students in 132 schools.
Poor schools may influence overweight adolescents in several ways beyond providing the unhealthy food choices at cafeterias that are typically blamed for adolescents being overweight, said Martin.
According to Martin and Frisco, who worked with Claudia Nau, a graduate student in sociology, and Kristin Burnett, of the U.S. Census Bureau, poor schools may not have the resources to pay for athletic and fitness programs. Better-funded schools may offer food choices that are unhealthy, but they may also have the means to provide additional healthy food options, such as vegetarian dishes, while schools with limited resources may rely more on vending machine income.
Stress also may play a role in the weight gain of students at poor schools.
"Schools with limited financial resources tend to be more stressful environments," said Martin. "Stress promotes weight gains and usually the worst kinds of weight gains." Stress tends to promote excess weight gain in the midsection, which is associated with such health problems as cardiovascular disease and type 2 diabetes.
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