Transition to diets that are high in saturated fat and sugar has caused a global public health concern, as the pattern of food consumption is a major modifiable risk factor for chronic non-communicable diseases. Although agri-food systems are intimately associated with this transition, agriculture and health sectors are largely disconnected in their priorities, policy, and analysis, with neither side considering the complex inter-relation between agri-trade, patterns of food consumption, health, and development. We show the importance of connection of these perspectives through estimation of the eff ect of adopting a healthy diet on population health, agricultural production, trade, the economy, and livelihoods,with a computable general equilibrium approach. On the basis of case-studies from the UK and Brazil, we suggest that benefits of a healthy diet policy will vary substantially between different populations, not only because of population dietary intake but also because of agricultural production, trade, and other economic factors.