As the British state labours under rising healthcare costs, attention has returned once more to the role of diet in public health and whether food behaviour should receive deeper intervention. This chapter explores the complex policy terrain of diet and health, suggesting some key drivers and lessons in history, as well as some major issues ahead. It proposes that a new ecological public health approach – linking health and environment, and thinking holistically – would refine strategy for getting the supply-chain to take health seriously. The alternative is for health to be left to the whims of the market, where public health spending will always be outclassed by big corporations' spending. Food as a public health concern has a chequered past in Great Britain, not least because the four nations that make up the UK have such varied cultures and histories as well as systems of food and public health governance.