The type, quantity and formats of foods we eat vary considerably over time and space. A person’s consumption of food is rarely a matter solely (or even largely) of personal conscious choice. Instead, it is affected by such wide-ranging factors as cultural identity and taboos, food availability and price, genetics, legislation, technological innovation and marketing campaigns. Governments and civil society organisations have long been promoting healthy diets to reduce the burden of noncommunicable diseases both at a global and national scale and the concept of ‘sustainable healthy diets’ – diets that have lower environmental impacts but fulfil nutritional requirements –  is very slowly gaining ground.