Location: Children's Nutrition Research CenterTitle: Change in dietary energy density after implementation of the Texas Public School Nutrition Policy Author
Submitted to: Journal Of The American Dietetic Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/1/2009
Publication Date: 3/1/2010
Citation: Mendoza, J.A., Watson, K., Cullen, K.W. 2010. Change in dietary energy density after implementation of the Texas Public School Nutrition Policy. Journal of the American Dietetic Association. 110(3):434-440. Interpretive Summary: Dietary energy density has been associated with obesity and risk for diabetes. This study assessed the impact of the Texas Public School Nutrition Policy on middle school students' lunchtime energy density before and after policy implementation. Energy density was defined in two ways: (1) foods only and no beverages, or (2) all food and beverages. After the policy, energy density decreased by both calculation methods. The Texas Public School Nutrition Policy was associated with desirable reductions in energy density, which suggests improved nutrient intake as a result of student school lunch consumption. Schools should consider enacting similar comprehensive nutrition policies to improve their students' lunch intake.
Technical Abstract: Consumption of energy-dense foods has been associated with rising obesity rates and the metabolic syndrome. Reducing dietary energy density is an important strategy to address obesity, but few studies have examined the effect of nutrition policies on children's energy density. The study's objective was to assess the impact of the Texas Public School Nutrition Policy on children's energy density by using a pre- and post-policy evaluation. Analysis of variance/covariance and nonparametric tests compared energy density after the Texas policy change to intakes at baseline. Two years of lunch food records were collected from middle school students in Southeast Texas at three public middle schools: baseline (2001-2002) and 1 year after implementation of the Texas Policy (2005-2006). Students recorded the amount and source of foods consumed. The Texas Public School Nutrition Policy was designed to promote a healthy school environment by restricting portion sizes of high-fat and high-sugar snacks and sweetened beverages, fat content of foods, and serving of high-fat vegetables like french fries. Energy density (kcal/g): energy density-1 was the energy of foods only (no beverages) divided by the gram weight and has been previously associated with obesity and insulin resistance; energy density-2 included all food and beverages to give a complete assessment of all sources of calories. Following implementation of the Texas policy, students' energy density-1 significantly decreased from 2.80+/-1.08 kcal/g to 2.17+/-0.78 kcal/g (P<0.0001). Similarly, energy density-2 significantly decreased from 1.38+/-0.76 kcal/g to 1.29+/-0.53 kcal/g (P<0.0001). In conclusion, the Texas Public School Nutrition Policy was associated with desirable reductions in energy density, which suggests improved nutrient intake as a result of student school lunch consumption.