A school meal study: comparing platewaste and likings of packed lunch and school lunch based on the New Nordic Diet

摘要

Background and objectives: The majority of Danish children do not eat in accordance with the national dietary guidelines. The OPUS School Meal Study is a school-based intervention study testing the health effects of the New Nordic Diet (NND). The aim of this sub-study was to compare edible plate waste and self-reported likings between packed lunch from home and the served NND meal.Methods: The OPUS School Meal study is a cluster-randomized controlled 2-period cross-over study consisting of two three-month periods: an intervention period (NND) and a control period. 187 children (8-11y) at two schools were assigned to the food waste sub-study. Edible plate waste was measured by weighing individually the meal for 5 consecutive days before and after lunch at the end of each dietary period. Self-reported smiley ratings from a web-based dietary assessment software for children were compared to edible plate waste. Data were statistical modelled in two steps, a generalised linear mixed model was fitted for the probability of waste/no waste, and secondly a model for positive waste data was fitted. Results: 74% of all meals (N=1558) had edible plate waste (5g). Looking at all lunches the odds for leaving edible plate waste was 11 times higher for NND than for packed lunch (P 0.001). Looking at the meals (N=1060) with edible plate waste the amount was not significantly different between meal types; the median (IQR) for NND was 85.0 (36.5; 150.0) and the median (IQR) for packed lunch 70.0 (40.0; 119.0). Lunches rated as ‘really bad’ or ‘bad’ in the self-reported likings had more waste than lunches rated ‘really good’ (P 0.001). Conclusions: The odds of having edible plate waste were significantly higher for NND meals compared to packed lunch. Liking of school meals are a significant determinant in order to reduce edible plate waste.