Exploring the evidence-to-practice gap in sustainable diet shift: the role of food practitioners in evidence use

Sustainable diet change, or shifting consumption behaviour toward environmentally sustainable and healthy diet choices, is one of the highest priorities for food systems change agendas. It is a widely researched topic, but implementing sustainable diet evidence into practice is still an ongoing challenge. The aim of this paper was to explore this evidence-to-practice gap by synthesising and applying theoretical knowledge from evidence-use and food systems literatures, along with empirical insights gleaned from food system actors, to explore the evidence-use process for sustainable diet research within the UK. The paper begins with a brief literature review to understand how evidence is used and put into practice and to investigate which food actors are involved as end-users in the evidence-use process for sustainable diet shift. We proposed the concept of food system ‘practitioners’ as individuals or organisations who are professionally involved in food system activities and influence, either directly or indirectly, food consumption behaviour. Through workshops and interviews, we explored the lived experiences of food practitioners using sustainable diet shift evidence. We presented our findings as themes of evidence discovery, evidence use, and evidence-use barriers, then developed an adapted evidence-use process model. Findings include: (1) evidence-use decisions were largely influenced by individual, contextual, and communication factors; (2) practitioners sought a clearer definition of sustainable diets and more practical recommendations; and (3) practitioners desired more defined institutional responsibility for food systems challenges. We concluded by summarising how this paper contributes to knowledge of evidence-to-practice gaps and providing implications for future research opportunities.