Drinking With Your Heart on Your Straw: Nudges to Entice Patrons to Choose Water over Soda

Abstract

Sugar sweetened beverage (SSB) consumption has been linked to death and disease worldwide and a major contributor to the obesity epidemic. The objective of this study was to utilize the mechanisms of Behavioral Economics to examine which type of nudge would be effective to entice customers to choose water instead of SSB. Three types of nudge interventions, with washout periods between, were used throughout the seven-week study. Posters with a nutrition (self-interest), charity (pro-social) or a combination of both nudges were displayed in an Italian-style fast-food franchise. Multi-level logistic regression was used to compare the proportions of customers who chose water across the three experimental conditions and controlled for fixed effects of day of week, cashier, and food order. Also assessed was if frequency of visits to the dining establishment moderated the effect of experimental condition on beverage choice. Multiple data points from the same customer were treated as repeated measures. There were 6,730 meals purchased by 2,393 unique customers. The nutrition (19.2%) and combination poster (18.3%) increased choice of water relative to the washout periods (13.2%), but the charity poster did not (13.1%). Beverage choice differed across day of the week (χ2=10.29, p=.04). There was a significant effect of cashier (χ2=83.74, p=<.001) and food order on water choice (χ2=41.05, p=<.001). Frequent diners were less influenced by the nutrition poster than less frequent diners (p=.046) but dining frequency did not moderate the effect of the charity and nutrition combination poster (p=.094). A nutrition nudge can be utilized in a food service operation to decrease SSB and increase water intake.