Immediate Beverage Reformulation and Sustained Consumer Behavior Change under Chile's Food Labeling Policies

Background Chile's front-of-package warning label law, implemented in phases beginning in 2016, aimed to reduce consumption of foods and beverages high in sugar, sodium, saturated fat, and calories. While previous studies have documented substantial reductions in sugar purchases following the policy, there is limited understanding of the mechanisms, particularly the relative contributions of producer and consumer responses. Method This study decomposes changes in the sugar content of beverage purchases into changes made by producers, such as reformulating, introducing, and discontinuing products, and changes in consumer purchasing, such as switching between products and changing the amount purchased. We use household purchase data from Kantar WorldPanel Chile from January 2015 to June 2019, merged with time-specific nutrition facts panel data, to conduct decomposition analyses of approximately 3500 beverage items across three policy periods: pre-policy, Phase 1 (July 2016-June 2018), and Phase 2 (July 2018-June 2019). Results Sugar from beverage purchases fell from 17.1 g/capita/day before the policy to 13.2 g/capita/day in Phase 1 and to 11.2 g/capita/day in Phase 2 (totaling 5.9 g/capita/day or 35% of the pre-policy level). In Phase 1, producer and consumer responses contributed roughly equally. Of the 3.9 g/capita/day fall in Phase 1, reduced purchase volumes accounted for 1.2 g and reformulation of continuing products for 1.1 g. Of the additional 2.0 g/capita/day fall in Phase 2, consumer responses dominated, with product switching accounting for 1.1 g/capita/day and reduced volumes for 0.8 g/capita/day, while reformulation contributed only 0.3 g/capita/day. Reductions were driven almost entirely by high-sugar beverages, with minimal reformulation among low-sugar beverages. Patterns were similar across socioeconomic groups, though the highest socioeconomic group saw a larger reduction in sugar purchases. Conclusion These findings demonstrate that nutrition labeling policies trigger both immediate producer reformulation and sustained consumer behavior change, highlighting the importance of considering both supply- and demand-side mechanisms in food policy design.