Energy-dense fast food products cost less: an observational study of the energy density and energy cost of Australian fast foods

Objective: To examine the association between energy cost and energy density of fast food products. Methods: Twenty Sydney outlets of the five largest fast food chains were surveyed four times. Price and kilojoule data were collected for all limited-time-only menu items (n=54) and a sample of standard items (n=67). Energy cost ($/kilojoule) and energy density (kilojoules/gram) of menu items were calculated. Results: There was a significant inverse relationship between menu item energy density and energy cost (p