title: School food environments and policies in US public schools.
abstract: OBJECTIVE
  The purpose of this study was to describe school food environments and policies in US public schools and how they vary according to school characteristics.
  
  
  METHODS
  We analyzed cross-sectional data from the third School Nutrition and Dietary Assessment study by using a nationally representative sample of 395 US public schools in 129 school districts in 38 states. These 2005 data included school reports of foods and beverages offered in the National School Lunch Program and on-site observations, in a subsample of schools, of competitive foods and beverages (those sold in vending machines and a la carte and that are not part of the National School Lunch Program). Seventeen factors were used to characterize school lunches, competitive foods, and other food-related policies and practices. These factors were used to compute the food environment summary score (0 [least healthy] to 17 [most healthy]) of each school.
  
  
  RESULTS
  There were vending machines in 17%, 82%, and 97% of elementary, middle, and high schools, respectively, and a la carte items were sold in 71%, 92%, and 93% of schools, respectively. Among secondary schools with vending and a la carte sales, these sources were free of low-nutrient energy-dense foods or beverages in 15% and 21% of middle and high schools, respectively. The food environment summary score was significantly higher (healthier) in the lower grade levels. The summary score was not associated with the percentage of students that was certified for free or reduced-price lunches or the percentage of students that was a racial/ethnic minority.
  
  
  CONCLUSIONS
  As children move to higher grade levels, their school food environments become less healthy. The great majority of US secondary schools sell items a la carte in the cafeteria and through vending machines, and these 2 sources often contain low-nutrient, energy-dense foods and beverages, commonly referred to as junk food.
authors.affiliation: Mathematica Policy Research, Inc, 955 Massachusetts Ave, Suite 801, Cambridge, MA 02139, USA. dfinkelstein@mathematica-mpr.com
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Finkelstein
authors.forename: Elaine L
authors.initials: EL
authors.lastname: Hill
authors.forename: Robert C
authors.initials: RC
authors.lastname: Whitaker
mesh_terms: D000293:Adolescent; D002648:Child; D003430:Cross-Sectional Studies; D005509:Food Dispensers, Automatic / Q000706:statistics & numerical data; D005522:Food Services / Q000458:organization & administration* / Q000592:standards / Q000706:statistics & numerical data; D006293:Health Promotion; D006801:Humans; D018673:Nutrition Policy; D009753:Nutritive Value; D012574:Schools; D012959:Socioeconomic Factors; D014481:United States; D016885:United States Department of Agriculture