Effects of Energy-Content Labels and Motivational Posters on Sales of Sugar-Sweetened Beverages: Stimulating Sales of Diet Drinks among Adults Study

This study examined the effects of an environmental intervention promoting more non–energy-containing beverage consumption compared to sugar-sweetened soft drink consumption through vending machines in an urban college setting. Eight soft drink vending machines were randomly selected and assigned to one of three conditions over a 9-week period: energy-content labels on non–energy-containing beverage selection panels (intervention I), labels plus motivational posters (intervention II), or control. The totals of all beverages sold and machine revenue were recorded at baseline (2 weeks), intervention (5 weeks), and postintervention (2 weeks) periods. Use of energy-content labels and motivational posters, compared with control group, resulted in a significantly lower growth rate of sugar-sweetened beverage sales (P<0.05). Total revenue for all beverages increased during the intervention period. It is estimated that the non–energy-containing beverages combined accounted for 70.52% of the increased revenue. Results of this study suggest that energy-content labels and motivational posters on beverage vending machines may be an effective way to influence beverage sales.