Meal types
Meals types were defined based on the source of protein that was included in a meal: meat-meals (further distinction between beef/lamb meals and poultry/pork meals), fish meals and vegetarian meals (further distinction between lacto-ovo meals or plant-based meals). In total, there were three main meal types (meat-based, fish-based and vegetarian meals) and five sub-meal types (beef or lamb-based, poultry or pork-based, fish-based, lacto-ovo and plant-based meals). We ranked the sources of protein on the basis of their environmental impact: beef or lamb > poultry or pork > fish > dairy or egg > plant-sourced protein [