A new take on sugary beverage taxation and calorie labeling: Does offering price discounts or presenting energy equivalent information change behavior?

Background: With mixed early evidence on the effectiveness of policies such as sugary beverage taxation and calorie-labeling, the objective of our study was to determine if (1) an alternative financial incentive—a price discount, and (2) an alternative presentation of calories – exercise equivalent messaging, would increase the sales of zero-calorie beverages and decrease the sale of sugary beverages. Methods: This was a national prospective trial with three hospital sites. Each site received five interventions: (1) a 10% price discount on zero-calorie beverages; (2)10% discount plus messaging promoting the discount; (3) messaging comparing calorie information of sugar-sweetened beverages with zero-calorie beverages; (4) messaging comparing exercise equivalent information (time necessary on a treadmill to expend calories); and (5) messaging comparing both calorie and exercise equivalent information. Poisson regression models were used to assess the association between sales of beverages and interventions. Results: Overall there were no significant effects on beverage purchases for any of the five interventions. Subgroup analyses revealed only one site with significant effects, which occurred during only two interventions: the discount and discount plus messaging interventions (purchases of sugary beverages decreased 10.5% (.004) and 10.3% (.008), respectively). However, these results were consistent with random chance under the null model. Discussion: The impact of price discounts and calorie and exercise equivalent messaging on purchasing of beverages was negligible in most settings. Our results suggest consumer behavior around beverage choice is not fully understood. Policies targeting these types of interventions warrant further evaluation before widespread implementation.