Study: Soda Tax Wont Curb Obesity

EVANSTON, Ill.Lawmakers in Illinois are considering a measure that would add a 1-cent per ounce tax to the cost of most sugar-sweetened beverages to help curb obesity; however, a new research paper presented at the U.S. Department of Agricultures (USDA) conference on food policy suggests the tax would have little impact because obese people tend to prefer artificially sweetened or diet drinks that would not be taxed under the law.

In his paper, Ketan Patel, a fourth-year doctoral student in economics at Northwestern University said analysis showed obese people like diet soda so much more than regular soda that you can do whatever you want to the price. "You're not going to get that much change in obese people's weight because they already drink diet soda," he said.

For this study, Patel used a large data set of sodas price and sales data with individual level data on demographic characteristics and body mass index (BMI) to estimate consumer preferences while allowing for substantial diversity in those preferences. After obtaining estimates of consumer preferences, Patel simulated how a tax would change the choices that consumers make and used the results of the simulation to estimate changes in weight using a weight change model from existing nutrition literature.

On June 9 the American Medical Associations (AMA) policy-making House of Delegates voted against supporting state taxes on sugar-sweetened beverages to fight obesity, saying it more information was needed on the topic. Some AMA members may want to broaden the concept to include taxes on juices, high caloric drinks, artificial sweeteners and sugars; however, several members said they were unlikely to support any taxes on sweetened beverages because they didn't favor "sin taxes" and opposed taxation as a way to influence consumer behavior.

"They said they were not sure that taxing these products would be appropriate and wanted to know more about the different types of sweeteners and their impact on public health. There will be a report back next year on the topic," said AMA Past President Dr. Cecil Wilson.

Economic analysis published last year by the Cato Institute suggested the causal link between the consumption of restaurant foods and obesity is minimal at best." The analysis suggested imposing a tax on high-calorie food and sugary beverages may not be an effective way for governments to tackle the obesity problem.