Impacts of the Seattle sweetened beverage tax on perceived healthfulness of sweetened beverages

Abstract

Sweetened beverage tax implementation is associated with differences in reduced purchasing volumes of sweetened beverages. However, it’s unclear whether the tax plays a role in shifting perceptions about sweetened beverages and their health impacts. We utilized pre-tax and post-tax survey data collected from Seattle and comparison area residents to compare differences in the perceived healthfulness of sweetened beverage consumption and drink types over time and across income groups. We found significant increases in the proportion of Seattle respondents with lower incomes who agreed that sweetened beverage consumption raises one’s chances of diabetes (DD = 0.09 (95% CI 0.05, 0.13); p = 0.002), heart disease (DD = 0.07 (95% CI 0.02, 0.12); p = 0.017), and serious health problems (DD = 0.12 (95% CI 0.05, 0.19); p = 0.009), above and beyond the changes in the comparison area. In contrast, we found significant decreases in the proportion of Seattle respondents with higher incomes, who agreed sweetened beverages raise one’s chances of serious health problems (DD = -0.07 (95% CI -0.11, -0.03); p = 0.009) and heart disease (DD = -0.07 (95% CI -0.13, -0.01); p = 0.038), compared to analogous changes in the comparison area. Perceptual changes regarding the negative health impacts of sweetened beverages appear most prominent among respondents with lower incomes in taxed, versus non-taxed, areas. These changes may be influenced by the combination of tax price effects and pro-tax educational outreach.