Application of theories of the policy process in research on consumption of sustainable diets: a systematic review

Background There is a significant global lack of policy action on consumption of sustainable diets. Application of political science theories such as theories of the policy process can help in understanding policy inaction. Applying these theories could provide a more in-depth understanding of how various influences on the policy process shape decision making for consumption of sustainable diet policy. Methods A systematic review to examine application of eight key political science theories of the policy process to research on consumption of sustainable diets was conducted. Results The review identified no papers applying a theory of the policy process although 17 papers did mention or discuss influences on the policy process that are common elements within theories of the policy process. Most notably these elements were the influence of coalitions/networks, evidence use, narratives and framing, institutional and political system factors, and the importance of value and belief systems and socio-cultural norms. However, in most papers these influences were not examined in a detailed or in-depth way and often presented as suggestions for lack of policy action without the support of empirical data or application of any theory. Conclusions Most research discussing policy inaction on the consumption of sustainable diets fails to utilise political science theories of the policy process, although a small number of papers include mention of or discussion of influences on the policy process. Application of political science theories could provide a more in-depth understanding of how different determinants might shape decision making at various points in the policy process. This could help identify key reasons for policy inaction on the consumption of sustainable diets and suggest possible ways to increase attention and action on the issue from policy decision makers.