The social welfare value of the global food system

The global food system provides nourishment to most of the world's eight billion people, generates trillions of dollars of goods and services, and employs more than one billion people. On the other hand, it generates substantial dietary health costs and environmental harms. Policymakers are asking about the overall contribution of the global food system to social welfare and how much larger it might be on a sustainable path. This paper describes our efforts to answer these questions. We couple multiple domain-specific models into a large-scale integrated assessment modelling framework capable of quantifying the outcomes of different food-system scenarios for incomes, health and the environment up to 2050, at a highly disaggregated level. We take these multi-dimensional outcomes and value them using a system of nested utility functions, building on recent work in environmental economics. We find that, relative to current trends, the bundle of measures in a Food System Transformation scenario would provide a large boost to global social welfare equivalent to increasing global GDP by about 7 %. Changes in income, environment and health all contribute positively. Measures to change diets are particularly beneficial, although a caveat is that our welfare estimates exclude possible consumer disutility from dietary changes. The results are robust to changes in key utility/damage parameters.