The health co-benefits of a global greenhouse-gas tax on food

The food sector is responsible for about a quarter of all greenhouse-gas (GHG) emissions, and significant changes in food production and patterns of food consumption are required in order for the food sector to make its pro rata contribution to climate change mitigation. At the same time, imbalanced diets, such as diets high in red and processed meat and low in fruits and vegetables are responsible for the greatest health burden globally and in most regions. Policy instruments that change the relative price of goods are among the most effective ways of influencing economic behaviour. Here we analyse the potential environmental and health impacts of a global GHG tax on foods levied at the point of purchase. For that purpose, we built a modelling framework consisting of agriculture, environmental, economic, and health aspects. In the framework, we used data from a global agriculture-economic model, the International Model for Policy Analysis of Agricultural Commodities and Trade, together with food-specific emissions data, and a global health model. Using the model framework, we find that levying GHG taxes on food commodities in 2020 could reduce food-related GHG emissions by 6%, generate tax revenues of USD 482 billion per year, and lead to 189,000 avoided deaths globally. However, special policy attention is needed in low-income countries (and possibly for low-income segments in other countries) to avert potential health losses associated with increased levels of underweight (and reduced consumption of fruits and vegetables). Tax policies sparing health-critical food groups, and policies aimed at compensating income losses associated with tax-related price increases are potential policy options that could help to avert negative health impacts for exposed populations, whilst incentivising the food sector to make its pro rata contribution to climate change mitigation.