A randomised control trial on the impact of nudges, information and incentives on food choices of vulnerable families

This study examines the impact of information, nudges and cash aid on food choices among vulnerable families receiving Red Cross aid in Spain. We use data on 1429 participants of a Randomised Controlled Trial (RCT) ran across 73 branches of the Red Cross in Catalonia, a region of Spain. While all RCT participants received cash-aid food vouchers, they were randomised to the following additional treatment arms: i) informational intervention about the benefits of healthy eating; ii) "affective" nudges reminding facts about healthy food, or iii) additional cash-aids. We use food purchasing data from all these participants who were also beneficiaries in 2023 of cash-aid food vouchers. We find a positive impact of all interventions aggregated in the three standard indexes of food purchasing quality. Examining intervention heterogeneity, we find that informational interventions and affective nudge messages were more effective than cash incentives in leading to healthier food choices. They improved the nutritional content, overall purchases and the quality of purchases made by the treated groups by 9.06 %, 3.29 % and 8.43 % of the average value for the control group during the pre-treatment period.