Objective: To examine characteristics potentially associated with school lunch fruit and vegetable waste, both overall and pre/post implementation of the Healthy, Hunger-Free Kids Act. Design: Multi-year (2010Multi-year ( -2013 cross-sectional study using pre-and post-meal digital photographs of students' school lunch trays to estimate fruit and vegetable availability and consumption. Fruit and vegetable items were categorized for factors suspected to impact waste: prior farm to school years, placement (main menu, salad bar), procurement (local, conventional), preparation (cooked, raw) and meal component (entrée, side, topping). Analyses to assess within-category differences in waste volume were performed using a Tobit model. Setting: Wisconsin elementary schools participating in farm to school programmes, USA. Subjects: Children in third to fifth grade. Results: Many within-factor differences were detected overall and/or across time. Cooked fruits were wasted less than raw, while cooked vegetables were wasted more than raw. Where identified, locally sourced items were wasted more than conventionally sourced (+0·1 cups, P < 0·0001) and salad bar items more than main menu items (+0·01 cups, P < 0·0001). Increasing prior farm to school years decreased waste (−0·02 cups, P < 0·0001). Items previously tried were wasted at the same volume whether reported as liked or not. New school lunch meal pattern requirement implementation did not uniformly impact fruit and vegetable waste across all categories and there was no change in waste for seven of fifteen assessed categories. Conclusions: Many factors impact elementary students' school lunch waste. These factors may be helpful for school food-service authorities to consider when planning school menus.
Keywords
Fruits and vegetables School lunch Food wasteThe prevalence of obesity among children and adolescents has grown over the past three decades, recently reaching 17 % (1-3) , over half of the adult obesity prevalence rate, which stood at nearly 36 % in 2009-2010 (3) . Obesity and related co-morbidities have public health as well as economic implications (4,5) . Because of this high prevalence, public health personnel and medical professionals emphasize the importance of consuming a healthy diet (6) . Few children meet consumption recommendations for fruit and vegetables (F&V) (7) . One strategy hypothesized to help achieve this is improving the quality of school meals. These efforts include promoting increased consumption of low-energy-density foods such as F&V which, on the basis of high water and fibre content, alongside their low fat content, collectively yield larger bulk and low energy density. Although the positive effects of low-energy-dense food have been demonstrated in adults (8) , the data are somewhat inconsistent, particularly among children (9)(10)(11) . While many factors influence dietary preferences and habits, encouraging children to consume recommended amounts of F&V is often part of programming conducted in schools (12)(13)(14)(15)(16)(17...