|Type of study||Method||Key findings|
|Systematic literature review ||This systematic review identified and synthesized the enablers and barriers to public policy change within the field of nutrition from peer-reviewed literature. Sixty three studies examining policymaking in public health nutrition in high income-democratic countries were included. An interpretive synthesis, involving induction and interpretation to identify key themes, was undertaken.||
• Political will is required for policy change|
• Public will is an enabler, but not essential for change
• Health professionals find it difficult to influence nutrition policy change
• Barriers and enablers do exist that may be of use to health professionals. These include: pressure from industry, neoliberal ideology, use of emotions and values, and being visible.
|Network analysis [16, 18]||Social network analysis techniques were used to explore the capacity of different individuals and interest groups to influence nutrition policymaking networks in Australia. Four rounds of data collection was undertaken and the capacity of individual actors and occupational categories e.g. food industry, nutrition academic, to influence policy decision-makers were analysed. Cluster analysis, and two measures of influence: path distance of actors from decision-makers and betweenness centrality, were also undertaken.||
• The food industry has the greatest capacity to influence nutrition policy in Australia compared to all other professional categories.|
• Nutrition professionals are far removed from key policy decision-makers, with limited strategic relationships.
• There are two key brokers, a general health professional from a non-government organisation and a nutrition academic, in the network that both play different brokerage roles.
|In-depth interviews ||Thirty seven nutrition policy decision-makers and key influencers were purposively selected to participate in semi-structured, in-depth interviews which examined the key barriers and enablers to nutrition policy change. Participants were chosen based on their ability to represent views from different ‘sides’ of the issue and obtain maximum diversity. They included health advocates, food industry senior executives, government policy officers, politicians and academics. Data analysis was undertaken using an adapted version of the Framework Method which included systematic coding, analysis and synthesis of the data to develop themes and categories .||
• Influencing nutrition policy is a complex and dynamic process with a series of inter-related barriers and enablers.|
• The strategy of investing in relationships underpinned the whole process.
• Crucial contextual factors (pressurised, risk-averse environment; system of governance; neoliberal environment; and the democratisation of knowledge) that also impact on nutrition policymaking in Australia were identified.