School canteens in Dijon, France: vegetarian meals have lower greenhouse gas emissions compared to non-vegetarian meals

In order to reduce environmental impacts of school canteen while respecting nutritional composition regulations, EGAlim law was adopted in France since 2018 to serve a weekly vegetarian meal in school canteens. However, meat-free meals are often perceived as inadequate to cover children’s nutritional needs. A recent study aims to assess the nutritional quality and greenhouse gas emissions (GHGE) of 249 vegetarian and non-vegetarian school meals served in primary schools in Dijon, France, in 2019. According to this work, increasing the frequency of vegetarian meals, by serving egg-based, dairy-based or vegan recipes more frequently, would reduce GHGE while maintaining adequate nutritional quality of primary school meals.

Tackling non-communicable diseases and environmental threats such as global warming, atmospheric and water pollution and deforestation are gaining interest globally. In this context, a shift towards a more sustainable food systems involving dietary changes are becoming essential to improve the nutritional quality and environmental impact of our diet (Clark et al., 2019 ; Willett et al., 2019). One of the effective levers to face this challenge is offering nutritious and environmentally friendly meals in school canteen, a place where social norms related to eating are established and where significant share of food are consumed by children (Coleman et al., 2021). In France, a law was adopted in 2018 (EGAlim) that includes measures related to school catering aiming to promote sustainable school meals (Légifrance, 2018). The objectives of EGAlim law were amended in 2021 by the Climate and Resilience by encouraging more vegetarian meals up to a daily vegetarian option at primary school canteens (Ministry of Food Agriculture, 2021).

While reducing animal proteins is key to building more environmentally friendly food systems, the challenge is to demonstrate that adequate nutritional quality could be maintained as a meat-free meal is often perceived as inadequate to cover children’s nutritional needs (Vieux et al., 2018). Therefore, the present study (Dahmani et al., 2022) aims to assess the nutritional quality and greenhouse gas emissions (GHGE) of 249 vegetarian and non-vegetarian school meals served in primary schools in Dijon, France, in 2019.

Description of nutritional quality and environmental impact of school meals

Total weight, energy content, the overall nutritional quality using the indicators “Mean Adequacy Ratio (MAR)” and “Mean Excess Ratio (MER)”, and environmental footprint indicators were calculated at the meal level. Figure 1 presents the description of meals.

Based on data from 249 meals:

• The average weight of a meal is 464 g;
• The average energy content of a meal is 659 kcal (i.e., 33%of the 2000 kcal/day recommended for children aged 6-11 years);
• The average MAR/2000 kcal was 88.3%, indicating that 88.3% of RDI for the 23 nutrients would be covered by 2000 kcal of a school meal;
• The average MER/2000 kcal was 19.1%, indicating that 19.1% of MRV for the 3 nutrients would be exceeded with 2000 kcal of a school meal;
• The average GHGE of a meal is 1.8 kgCO2 eq.

Increasing the frequency of vegetarian meals would reduce GHGE while maintaining adequate nutritional quality

Among the 249 school meals included in the present study, 73,5% were non-vegetarian (n=183) and 26,5% were vegetarian (n=66). The analysis showed that vegetarian and non-vegetarian meals had similar weights and energy contents. In addition, both vegetarian and non-vegetarian school meals had a similar nutritional quality, as the following:

• MAR/2,000 kcal= 87.5% for vegetarian, and 88.5% for non-vegetarian meals
• MER/2,000 kcal= 19.3% for vegetarian, and 19.1% for non-vegetarian meals

However, when comparing 5 meal subcategories based on protein dish, MAR/2,000 kcal and MER/2,000 kcal were significantly lower for meals with vegan dishes compared to meals with fish dishes or eggs and/or cheese dishes.
As regards environmental footprint, a vegetarian meal emitted 0.9 kgCO2eq, whereas a non-vegetarian meal emitted 2.1 kgCO2eq, showing that GHGE were more than twofold reduced in vegetarian compared to non-vegetarian meals. GHGE was the highest for meals with beef, veal or lamb followed by meals with fish, meals with pork or poultry, meals with eggs and/or cheese and finally vegan meals.
Therefore, increasing the frequency of vegetarian meals, by serving egg-based, dairy-based or vegan recipes more frequently, would reduce GHGE while maintaining adequate nutritional quality of primary school meals.

Future works should consider other dimensions of sustainable food systems

In the present study, only nutritional indicators and one environmental indicator (i.e., GHGE) were assessed. Other environmental indicators such as eutrophication, acidification, toxicity, biodiversity were not considered, neither the bioavailability of nutrients (e.g., bioavailability of iron and zinc are lowered when provided from plant-based products.

It is also essential to include other indicators reflecting different dimensions of sustainable food systems such as attendance at school canteens, food waste, meal cost and children’s liking of meals. This would help to provide a holistic view to move toward more sustainable school meals.

Based on: Dahmani J, et al. Nutritional quality and greenhouse gas emissions of vegetarian and non-vegetarian primary school meals: A case study in Dijon, France. Front Nutr. 2022 Oct 10;9:997144.