Food and Beverage Promotions in Minnesota Secondary Schools: Secular Changes, Correlates, and Associations with Adolescents' Dietary Behaviors.

Reducing consumption of energy-dense, nutrient-poor foods and beverages is a key target of efforts to reverse the obesity epidemic and prevent related chronic disease.1 To achieve Healthy People 2020 goals for reducing adolescent obesity, it is estimated an average reduction of 72 kcal/day would be required.2 The ubiquitous availability and marketing of energy-dense foods and beverages in settings where young people spend their time detrimentally influence the dietary patterns of adolescents and have thus become of public health concern.3 Young people are particularly vulnerable to food and beverage marketing before they develop a strong understanding of healthy eating principles, fully develop their ability to recognize persuasive intent, and consistently apply this knowledge as a cognitive defense to the messages which permeate their lives.4 School settings are a particular focus of concerns because of the amount of time young people spend at school and the legitimacy lent to advertising and all forms of marketing when allowed by policymakers, administrators, and other stakeholders. A congressionally requested report released in 2005 challenged school stakeholders to develop policies and practices that limit student exposure to promotions for energy-dense, nutrient-poor products and to improve the availability and marketing of healthy options.3 Evidence exists that efforts to reduce the availability of energy-dense, nutrient-poor products in schools have achieved some success. National data recently showed a decrease in the availability of vending machines in middle schools and an increase for both middle and high schools in the implementation of nutritional guidelines for competitive foods and beverages.5 However, relatively little is known regarding trends over time or factors influencing the implementation of school policies and practices designed to limit student exposure to advertising for energy-dense, nutrient-poor products sold within and outside of school environments. Complimentary knowledge of school practices designed to promote the selection of healthy, nutrient-dense options such as fruits/vegetables and low-fat milk is even more scant. Research regarding secular changes, influences on implementation, and the effectiveness of pertinent school policies and practices in the absence of federal or state-level policies is needed to guide future public health efforts. The current study was designed to help fill these identified research gaps using data on public middle schools and junior/senior high schools in Minnesota. The first aim was to examine secular changes from 2008 to 2012 in school policies relating to the advertising of energy-dense, nutrient-poor products as well as the degree to which schools made environmental changes to promote healthy food and beverage choices by 2012. Overall changes were examined as well as school-level demographic differences during this period in which there was growing research and regulatory attention on marketing. The second aim was to assess whether school-level efforts to coordinate health improvements were related to advertising policies or the promotion of healthy foods and beverages. In addition, a third aim was to describe associations between advertising policies, healthy food and beverage promotions, and students’ dietary behaviors.