UC Berkeley

Objectives

To estimate changes in sugar-sweetened beverage (SSB) and water consumption 3 years after an SSB tax in Berkeley, California, relative to unexposed comparison neighborhoods.

Methods

Data came from repeated annual cross-sectional beverage frequency questionnaires from 2014 to 2017 in demographically diverse Berkeley (n = 1513) and comparison (San Francisco and Oakland; n = 3712) neighborhoods. Pretax consumption (2014) was compared with a weighted average of 3 years of posttax consumption.

Results

At baseline, SSBs were consumed 1.25 times per day (95% confidence interval [CI] = 1.00, 1.50) in Berkeley and 1.27 times per day (95% CI = 1.13, 1.42) in comparison city neighborhoods. When we adjusted for covariates, consumption in Berkeley declined by 0.55 times per day (95% CI = -0.75, -0.35) for SSBs and increased by 1.02 times per day (95% CI = 0.54, 1.50) for water. Changes in consumption in Berkeley were significantly different from those in the comparison group, which saw no significant changes.

Conclusions

Reductions in SSB consumption were sustained in demographically diverse Berkeley neighborhoods over the first 3 years of an SSB tax, relative to comparison cities. These persistent, longer-term reductions in SSB consumption suggest that SSB taxes are an effective policy option for jurisdictions focused on improving public health.