A new study of the soda tax in Berkeley, Calif., shows that residents are doing what public health experts had hoped — they’re ditching sugary drinks and opting for healthier beverages.
The study, the largest to date of Berkeley’s soda tax, comes as California lawmakers this week again consider legislation to put a warning label on sweetened beverages — a bill that died in committee three times in three years.
The study, published Tuesday in the journal PLOS Medicine, shows that a year after Berkeley’s soda tax took effect in 2015, the city saw a nearly 10 percent drop in purchases of sugary drinks and a nearly 16 percent increase in sales of bottled water.
The study looked at 15.5 million supermarket checkouts in the city, evaluated prices in 26 stores and surveyed 957 adult residents by phone.
Dr. Lynn Silver, the lead author of the study and a senior adviser with the Public Health Institute in Oakland, Calif., said that researchers were pleasantly surprised to see the significant increase in the sale of water.
Silver said that before voters passed the 1-cent-per-fluid-ounce tax in 2014, researchers were not sure if the small additional cost to buy soda would be enough to make a difference in a prosperous city like Berkeley. But the study’s findings show that it’s “been a home run,” she said.
However, while purchases of sugary drinks dropped in Berkeley, they rose in surrounding Bay Area cities by 6 percent — prompting the question of whether residents simply shifted their soda buying to other cities without a soda tax. Silver said that residents surveyed did not report significant changes in where they purchased their beverages after the tax took effect.
The study, Silver said, also showed that overall beverage sales went up in Berkeley. If people were buying beverages elsewhere, that overall number would have most likely dropped, she explained.
Last year, voters approved a similar soda tax in San Francisco, Oakland and Albany, Calif., as well as in Boulder, Colo., Cook County, Ill., and Philadelphia. Santa Fe, N.M., and Seattle are considering soda taxes.
Researchers believe soda taxes in those communities could have a greater impact than in Berkeley because per capita consumption of sweetened beverages is about three times lower in Berkeley than the country as a whole, Silver said.
Meanwhile, in the California Legislature, a bill reintroduced by Sen. Bill Monning (D-Carmel) would require that sugar-sweetened drinks of 75 calories or more per 12 ounces be labeled with the following message:
STATE OF CALIFORNIA SAFETY WARNING: Drinking beverages with added sugar(s) contributes to obesity, type 2 diabetes, and tooth decay.
“Consumers have the right to know about these potential harmful health impacts, and [this bill] will empower Californians to make healthy beverage choices,” Monning said in a press statement.
The bill also would require owners of vending machines selling sugary drinks to place a safety warning on the machines’ exteriors.
A spokeswoman for the American Beverage Association, an industry group, said in an emailed statement that consumers have more information than ever before to make informed food and beverage choices.
“Singling out one common grocery item for a misleading warning label will do nothing for real public health challenges like obesity and diabetes, which have multiple risk factors,” the spokeswoman wrote.
If the bill passes, labeling would be required starting July 1, 2018. The legislation is scheduled for a hearing on Wednesday in the Senate Health Committee.
This story was produced by Kaiser Health News, which publishes California Healthline, an editorially independent service of the California Health Care Foundation.
