The Impact of a Sweetened Beverage Tax on Beverage Volume Sold in Cook County, Illinois, and Its Border Area

Sugar-sweetened beverage (SSB) consumption is linked to adverse health outcomes.

To evaluate the impact of the 2017 Cook County, Illinois, Sweetened Beverage Tax (SBT) on the volume of taxed and untaxed beverages sold in Cook County and its 2-mile border area.

Pre-post intervention-comparison site difference-in-differences study.

Cook County, Illinois, and St. Louis City and County, Missouri, 2016 to 2017.

Universal product code-level store scanner data from supermarkets and grocery, convenience, drug, mass merchandise, and dollar stores.

Beverage volume sold of taxed and untaxed beverages, across product categories and sizes.

Volume sold of taxed beverages decreased by 27% (ratio of incidence rate ratios [RIRR], 0.73 [95% CI, 0.70 to 0.75]) on average in Cook County relative to St. Louis during the 4 months that the SBT was in effect (compared with the same 4-month pretax period), with a net decrease of 21% after increases in volume sold in its border area (cross-border shopping) were taken into account. The magnitude of the decrease in volume sold across types of taxed beverages was heterogeneous: -32% (RIRR, 0.68 [CI, 0.65 to 0.72]) for soda versus -11% (RIRR, 0.89 [CI, 0.82 to 0.97]) for energy drinks, -37% (RIRR, 0.63 [CI, 0.59 to 0.66]) for artificially sweetened beverages versus -25% (RIRR, 0.75 [CI, 0.72 to 0.79]) for SSBs, and -29% (RIRR, 0.71 [CI, 0.68 to 0.74]) for family-size versus -19% (RIRR, 0.81 [CI, 0.79 to 0.84]) for individual-size beverages. There was no significant change in volume sold of untaxed beverages in Cook County or its border area.

Data source did not allow for evaluation by store type or distance of outlets from the border.

The Cook County SBT led to a substantial reduction in the volume sold of taxed beverages in Cook County. Part of this effect was offset by cross-border shopping. Cross-border shopping was limited to tax avoidance and did not extend to untaxed beverages.

Bloomberg Philanthropies.