The 21 percent decline in consumption of sugar-sweetened beverages (SSB) following implementation of a soda tax in Berkeley “has important public health implications, providing I think the strongest evidence so far that a tax would reduce SSB consumption,” writes Parke Wilde, an associate professor at Tuft’s Friedman School of Nutrition at his blog U.S. Food Policy. The effect was found in a study published in the the American Journal of Public Health this month.
Parke, an economist, notes that many of his colleagues were skeptical of the effect such a tax would have. “There is a long tradition in my profession of doubting the potential impact of such taxes,” Wilde writes. Many were quoted in a Washington Post article in 2015. Now, at least one of them is dialing back, writing: “I’m more than willing to accept the finding that the Berkeley city soda tax caused soda consumption to fall. The much more difficult question is: are Berkeley residents better off?”
Parke noted that a typical elasticity estimate for soda is about -1.2, meaning that the price increase in Berkeley (about 8 percent) would have been expected to generate a consumption decline of about 10 percent. “The authors took care to confirm that the estimated consumption decline of 21 percent was significantly different from zero, which is the standard statistical way of making sure the estimates were not a random statistical fluke.”
Meanwhile, Politico reports that the soda industry is already spending heavily for battles in San Francisco, Oakland and other cities this November over soda tax ballot measures. “The beverage industry has reserved $9.5 million of TV air time in the San Francisco media market. It’s an early move to ensure tax opponents have air space in a cycle where city voters will consider dozens of other ballot initiatives,” Politico writes. In Oakland industry has spent nearly $750,000 on consulting services and advertisements, “which is many times more than has ever been spent on a ballot measure there.”