We will investigate if the provision of information about CO2 emissions connected to own food purchases influences food purchases. Concretely, we will invite a randomly selected representative sample (drawn by Statistics Denmark, n=50.000) of Danes to participate in the study. The selected individuals will be invited through the official public digital mailing platform in Denmark (called E-boks) based on their social security number. Different versions of the invitation letter will be randomized among the sample. The basic version is written in neutral terms explaining the project, another version of the invitation will, in addition to the neutral description, mention the projects’ importance for the climate, yet a third will add the economic benefit associated with the project for the participants.
If the participants accept the invitation, they sign-up to the study by answering a short questionnaire on health, economic, climate and food-security issues related to food consumption. This questionnaire appears on the project website (created in Qualtrics), where further instructions about the project are also provided. After being enrolled into the project, the participants are randomized into one of three different treatments. In one treatment, they are asked to download and register on an app providing an economic overview of their food purchase (called Spenderlog). In a second treatment, they are asked to download and register on an app which gives an overview of the CO2 emission resulting from their food purchase (called Co2Food). In a third group, they are asked to download both apps. Our aim is to compare the food purchases in the groups before and during the intervention.