Number of meal components, nutritional guidelines, vegetarian meals, avoiding ruminant meat: what is the best trade-off for improving school meal sustainability?

Abstract

PurposeSchool meals have the potential to promote more sustainable diets. Our aim was to identify the best trade-off between nutrition and the environment by applying four levers to school meals: i) reducing the number of meal components, ii) complying with the French school nutritional guidelines, iii) increasing the number of vegetarian meals, and/or iv) avoiding ruminant meat. MethodsLevers were analyzed alone or in combination in seventeen scenarios. For each scenario, 100 series of 20 meals were generated from a database of 2316 school dishes using mathematical optimization. The nutritional quality of the series was assessed through the Mean Adequacy Ratio (MAR/2000 kcal). Seven environmental impacts were considered such as greenhouse gas emissions (GHGE). One scenario, close to series usually served in French schools (containing 4 vegetarian meals, at least 4 ruminant meat-based meals, and at least 4 fish-based meals) was considered as the reference scenario. ResultsReducing the number of meal components induced an important decrease of the energy content but the environmental impact was little altered. Complying with school-specific nutritional guidelines ensured nutritional quality but slightly increased GHGE. Increasing the number of vegetarian meals decreased GHGE (from -11.7% to -61.2%) but decreased nutritional quality, especially when all meals were vegetarian (MAR= 88.1% against 95.3% in the reference scenario). Compared to the reference scenario, series with 12 vegetarian meals, 4 meals containing fish and 4 meals containing pork or poultry reduced GHGE by 50% while maintaining good nutritional quality (MAR=94.0%). ConclusionUpdating French school nutritional guidelines by increasing the number of vegetarian meals up to 12 over 20 and serving non-ruminant meats and fish with the other meals would be the best trade-off for decreasing the environmental impacts of meals without altering their nutritional quality.

Nutritional quality and greenhouse gas emissions of vegetarian and non-vegetarian primary school meals: A case study in Dijon, France

“…In a context where reducing GHGE from the food system is necessary and urgent to meet the Paris Agreement's goal of limiting the increase in global temperature to 1.5 or 2 • C (40), we highlighted that lowering GHGE of school meals can be done without damaging consequences on children's health. Consistent with this idea, the results of a recent study showed that the best trade-off would be a series of 20 meals with 12 vegetarian, four fish-based and four pork-or poultry-based meals (23). Beyond school meals, recent evidence suggested that there are no specific nutritional risk in vegetarian children (41) and no clinically meaningful differences in growth or biochemical measures in vegetarian children (42).…”

“…It also raises the question of potential degradation of nutritional quality, as suggested by Vieux et al ( 16 ), although nutrient profiling methods have shown that vegetarian and non-vegetarian main dishes offered in primary schools in France were generally of good nutritional quality ( 22 ). In addition, a recent simulation study based on a database of 2,316 school dishes demonstrated that the best trade-off for decreasing the environmental impacts of school meals without altering their nutritional quality was a frequency of 12 vegetarian meals over a total of 20 meals ( 23 ).…”

Interventions to Strengthen Environmental Sustainability of School Food Systems: Narrative Scoping Review

“…The dates of publication ranged from 2011 to 2022. The majority of interventions were undertaken in Europe: Spain [26][27][28][29][30][31], Sweden [32][33][34][35], France [36,37], England [38,39], Finland [40] and Denmark [41]. Four were undertaken in the USA [42][43][44][45][46], one in Mexico [47] and one in Australia [48].…”

“…Four were undertaken in the USA [42][43][44][45][46], one in Mexico [47] and one in Australia [48]. Seventeen of the studies used quantitative methods only to evaluate their intervention to promote the sustainability of the food system [26][27][28][29]32,[34][35][36][37][38][39][40][41][43][44][45][46]49], four used qualitative methods only [33,42,47,50] and two used a mixed methods approach [30,48].…”

“…Of the studies which used quantitative or mixed methods (n = 20), a range of study designs was identified, the most common being a pre-post design without a control group comparator [34,35,38,[44][45][46]48,49]. Five were modelling studies [26][27][28][29]36], three used a pre-post design with a comparator [30,32,40], two used a cross-over design [37,41], one used a historical control [39] and one used a cluster randomised trial design [43]. The studies that used qualitative methods only differed in their approach, with one undertaking focus groups only [33], one conducting semi-structured interviews only [50], one using an action research approach [47] and another using interviews, focus groups and observation with a case study design [42].…”