The effectiveness of food system policies to improve nutrition, nutrition-related inequalities and environmental sustainability: a scoping review

A global transformation of food systems is needed, given their impact on the three interconnected pandemics of undernutrition, obesity and climate change. A scoping review was conducted to synthesise the effectiveness of food system policies/interventions to improve nutrition, nutrition inequalities and environmental sustainability, and to identify double- or triple-duty potentials (their effectiveness tackling simultaneously two or all of these outcomes). When available, their effects on nutritional vulnerabilities and women's empowerment were described. The policies/interventions studied were derived from a compilation of international recommendations. The literature search was conducted according to the PRISMA extension for scoping reviews. A total of 196 reviews were included in the analysis. The triple-duty interventions identified were sustainable agriculture practices and school food programmes. Labelling, reformulation, in-store nudging interventions and fiscal measures showed double-duty potential across outcomes. Labelling also incentivises food reformulation by the industry. Some interventions (i.e., school food programmes, reformulation, fiscal measures) reduce socio-economic differences in diets, whereas labelling may be more effective among women and higher socio-economic groups. A trade-off identified was that healthy food provision interventions may increase food waste. Overall, multi-component interventions were found to be the most effective to improve nutrition and inequalities. Policies combining nutrition and environmental sustainability objectives are few and mainly of the information type (i.e., labelling). Little evidence is available on the policies/interventions' effect on environmental sustainability and women's empowerment. Current research fails to provide good-quality evidence on food systems policies/interventions, in particular in the food supply chains domain. Research to fill this knowledge gap is needed.