A sweet drink sign is laid out of sweet drinks at a supermarket in the Port Richmond area of Philadelphia, Wednesday, July 18, 2018.
Matt Slocum | AP
Sugary drink sales dropped 38% in Philadelphia after the city began taxing sodas and other sweet drinks in 2017, according to a study published Tuesday in the Journal of the American Medical Association.
Philadelphia imposed a tax of 1.5 cents per ounce on sweet drinks beginning January 1
Supporters claim that sodas can discourage people from indulging in sugary drinks, and possibly helping to curb obesity, diabetes, and other diet-related conditions. Critics say governments should not dictate what people drink, and raising the price of a city will only cause people to shop elsewhere. While drinking at Philadelphia city limits dropped by 51%, it was partly offset by an increase in sales just outside the city, resulting in a net drop in noise sales of 38% in the area, researchers at the University of Pennsylvania found.
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To measure how Philadelphia's tax impacted sales of sugary drinks, researchers analyzed scanner data from market research firm IRI during the year before the tax came into force and the following year. They analyzed sales in Philadelphia, neighboring communities and Baltimore, which served as a control group. They did not study people's actual consumption habits or health outcomes.
"When we think about what it really is going to do to reduce chronic illness in this country, including diabetes, obesity and obesity, we need massive measures and the evidence is very strong, this is one that works," Dr said. Kristine Madsen, faculty director of the Berkeley Food Institute at the University of California Berkeley, who was not involved in the study, but wrote an accompanying editorial.
Researchers track sales in 291 chain stores, grocery stores and mass market stores. The results do not include independent stores. The researchers analyzed sales in the retailers for a separate survey, which is under consideration and has not yet been published.
Bloomberg Philanthropies, backed by billionaire, former mayor of New York, Michael Bloomberg, funded the study. Bloomberg attempted to impose a partial ban on soda, while the mayor and personally greeted millions in lobbying for sodas.
Christina Roberto, assistant professor of medical ethics and health policy at the Perelman School of Medicine at the University of Pennsylvania and lead author, said the researchers are "independent" and the organization had "no role" in the study.
"It's such a big and obvious effect, it's hard to spin this," Roberto said. "The data is so clear and obvious."
William Dermody, spokesman for the American Beverage Association, said in a statement: "It is evident from this survey and that others who drink tax damage work families, small local businesses and their employees."
"Many Filipinos avoid tax by buying drinks outside the city, "he said, pointing to a study published last year, showing that sales pitches in a soda cat city were compensated by people who bought sugary drinks outside the city.