Berkeley’s soda tax, which is now in its 5th year, has been a resounding success. The tax initiative has allowed Berkeley to invest over $5 million in public health programs, especially for children and African American, Latinx, and low-income communities. The new programming includes work on diabetes prevention, water access, oral health, and nutrition education. The tax also saved our public schools’ renowned Gardening and Cooking Program from being cut.

And the tax has brought down sugary drink consumption. Our study of the tax focused on lower-income communities of color that have been disproportionately targeted by sugary drink ads and suffer higher rates of diabetes. After surveying residents of these communities in Berkeley and nearby cities before and after the tax, we found a 52% drop in consumption of sugary drinks in Berkeley in the first three years of the tax. Other research evaluating Berkeley’s tax used grocery store sales data and found significant drops in sugary drink purchases.

One might think we could also use the city’s soda tax revenues to see if the tax changed consumption. But that’s wrong, and here’s why. To see a change, we need sales or consumption information before and after the tax. Tax revenues cannot capture sales before the tax for one simple reason: There was no tax revenue before the tax. Several studies of the tax that did collect before- and after- data, including ours, found early and sizeable drops in consumption. Other factors may keep total tax revenues stable, even as residents drink fewer and fewer sugary drinks. These include Berkeley’s growing student and overall populations and the visitors who buy drinks—but don’t live—in Berkeley. For these reasons, Berkeley’s gross tax revenues cannot tell us if the tax was effective.

Multiple independent studies of Berkeley’s soda tax clearly show that the tax brings down consumption, as do studies of soda taxes in other places. Whether using consumption data from residents or purchase data from store scanners, the research consistently demonstrates marked declines in sugary drink consumption and sales after a soda tax, including in Philadelphia and Mexico. Prominent health organizations resoundingly agree. They have called for soda taxes to help combat the crises of diabetes, cardiovascular disease, and poor oral health. These groups include The American Heart Association, American Academy of Pediatrics, American Cancer Society, California Dental Association, California Medical Association, the World Health Organization, and many more.

The Berkeley soda tax has reduced sugary drink consumption and sales while providing sorely needed revenues to improve the health and well-being of Berkeley’s children—exactly as voters intended.

This is the first part of a two-part series on Berkeley’s soda tax. Read part two here.

Jennifer Falbe is an assistant professor at UC Davis, a Berkeley resident, and a researcher studying the Berkeley soda tax
Jennifer Falbe is an assistant professor at UC Davis, a Berkeley resident, and a researcher studying the Berkeley soda tax