Promoting plant-based eating in meat-centric meal contexts: a field study.

OBJECTIVE: Shifting from meat-centric to plant-rich diets may help to enable healthier and more sustainable food systems. Here we present the results of a 1-week intervention to promote plant-based eating in a meat-centric food context (i.e. canteen). DESIGN: The intervention included environmental restructuring strategies (e.g. promotional materials and menu redevelopment) and improvements to the offer of plant-based meals. The evaluation (sales data; pre-registered) spanned 3 weeks prior to the intervention (baseline), 1 week during the intervention (immediate/short-term impact) and 3 weeks after the intervention (follow-up). Opinion surveys were also used to collect data with customers during the intervention. SETTING: Canteen unit of a university campus in Portugal (Lisbon metropolitan area). PARTICIPANTS: In addition to sales data (baseline: 7965 meals; immediate/short-term: 2635 meals; follow-up: 7135 meals), we used opinion surveys to assess customers' meal appraisals during the intervention (n = 370). RESULTS: The odds of a sold meal being vegetarian were 24 % higher in the intervention week compared with the pre-intervention period [OR = 1·24, 95 % CI (1·10, 1·40)] and 9 % higher in the post-intervention period compared with the pre-intervention period [OR = 1·09, (95 % CI (1·00, 1·19)]. Survey data showed that vegetarian meals compared favourably to meat and fish alternatives in liking, sustainability and satiety. CONCLUSIONS: A short-term, theory-driven, operationally feasible intervention was effective in promoting increased plant-based meal choices in a collective meal context. Nevertheless, these changes were not entirely sustained over time. Future studies could test whether prolonged or more transformative interventions are necessary to unlock entrenched food practices more effectively in meat-centric collective meal contexts.

How to enable healthier and more sustainable food practices in collective meal contexts: A scoping review.

Collective meal contexts such as restaurants, cafeterias and canteens can help accelerate transitions to healthier and more sustainable diets. However, evidence from intervention studies on these contexts lacks integration. This scoping review aimed to map determinants of dietary change in collective meal contexts across multiple settings, interventions, target groups, and target behaviors. The review provided two main outcomes: (i) identifying intervention components to promote dietary change in collective meal contexts, based on the existing body of evidence; and (ii) classifying and integrating these intervention components into an overarching framework of behavior change (i.e., COM-B system). The review encompassed twenty-eight databases via two indexing services and extracted information from 232 primary sources (27,458 records selected for title and abstract screening, 574 articles selected for full-text screening). We identified a total of 653 intervention activities, which were classified into intervention components and grouped under three broad themes, namely contextual and environmental changes, social influence, and knowledge and behavioral regulation. Multi-component interventions tended to report overall positive outcomes. The review proposes several directions for future research, including: (i) moving toward more theory-based interventions in collective meal contexts; (ii) providing more detailed information about intervention settings, implementation, target groups, activities, and materials; and (iii) improving the use of open science practices in the field. Furthermore, the review offers a free, original, open-access list and synthesis of 277 intervention studies in collective meal contexts, which can help intervention planners and evaluators optimize their efforts to promote healthier and more sustainable food practices in these contexts.