Impact of the Philadelphia Beverage Tax on Perceived Beverage Healthfulness, Tax Awareness, and Tax Opinions

Objective To assess the impact of the Philadelphia Beverage Tax on perceived beverage healthfulness, and awareness and opinions of the tax. Design Natural experiment Setting Small independent stores in Philadelphia (n = 61) and Baltimore (untaxed control site; n = 65) Participants Shoppers in Philadelphia (n = 2,731) and Baltimore (n = 4,600) pre- and post-tax implementation. Main Outcome Measures Perceptions of 4 beverages (unhealthy vs healthy/neutral), tax awareness, and tax opinions (oppose vs favor/neutral). Analysis Mixed-effects linear probability models estimated changes in perceived beverage healthfulness in Philadelphia, relative to Baltimore, following a difference-in-differences approach. Mixed-effects linear probability models estimated pre-post changes in tax awareness and opinions in Philadelphia-only. Results The probability of perceiving taxed beverages as unhealthy increased 2-years post-tax relative to Baltimore (regular soda: 5.7% [95% confidence interval (CI), 0.9–10.6], P = 0.02; diet soda: 7.7% [95% CI, 1.5–13.8], P < 0.001; sports drinks: 6.4% [95% CI, 0.4–12.4], P = 0.04), with similar changes at 1-year post-tax, whereas perceived healthfulness of untaxed 100% fruit juice did not change. Tax awareness was high at baseline (72%) and increased post-implementation; however, the probability of opposing the tax (22%) also increased over time. Conclusions and Implications Decreases in the perceived healthfulness of taxed beverages suggest the tax had a health-signaling effect. Consumer awareness and health education efforts could complement tax policies to enhance understanding of health risks.