State but not district nutrition policies are associated with less 'junk food' in school vending machines and school stores in US public schools

Purpose: To determine whether state- and district-level nutrition policies addressing junk food (JF) sales to students in school vending machines and school stores (SVMSS) were associated with less JF availability in SVMSS. JF was defined as foods/beverages with low-nutrient density, providing calories primarily through fats/added sugars, with minimal vitamins/minerals.

Methods: Logistic regression adjusted for school characteristics and sampling weights was used to analyze cross-sectional data from a nationally representative sample of 563 public schools (38% elementary, 29% middle, 33% high schools) participating in the School Health Policies and Programs Study (SHPPS) 2006. Policies were assessed for strength (required, recommended, neither-required-nor-recommended prohibiting JF sales) and whether strength was similar for SVMSS. JF was dichotomized as YES (school sold any JF) versus NO (no food or no JF sold)

Results: SVMSS were more prevalent in high schools (93%) than middle (83%) and elementary (26%) schools. Elementary schools with state polices that either required (13% versus 37%; p=0.002) or recommended (22% versus 37%; p=0.08) prohibiting JF sales in SVMSS offered less JF than elementary schools with state policies that neither-required-nor-recommended JF sales. Middle schools with state policies that required prohibiting JF sales in SVMSS offered less JF than middle schools with state policies that recommended prohibiting JF sales (71% versus 87%; p=0.05). Similar associations were not evident for district-level policies or for high schools.

Conclusions: Policy may be an effective tool to decrease JF availability in schools, particularly elementary and middle schools. The lack of promising results for district-level policy and among high schools requires further attention.