Taxing Sugary Beverages Not Clear Cut Strategy to Reduce Obesity

Taxing sugary beverages may help reduce calories from these beverages in the United States, but the health benefits may be partially offset as consumers substitute with other unhealthy foods, according to a joint study by researchers at RTI International, Duke University, and the US Department of Agriculture.

The study, published online in the American Journal of Agricultural Economics, found that a half-cent per ounce increase in sugar-sweetened beverage prices, which adds up to about ten cents on a typical 20-oz bottle of soda, could reduce total calories from the 23 foods and beverages examined under the study.

However, researchers found the reduction in sugary beverages due to a soda tax would likely lead consumers to substitute for those beverage calories by increasing their calorie, salt, and fat intake from untaxed foods and beverages.

“Instituting a sugary beverage tax may be an appealing public policy option to curb obesity, but it’s not as easy to use taxes to curb obesity as it is with smoking,” says Chen Zhen, PhD, a research economist at RTI, and the paper’s lead author. “Consumers can simply substitute an untaxed high calorie food for a taxed one. And as we know, reducing calories is just one of many ways to promoting healthy eating and reducing nutrition-related chronic disease.”

The study also examined differences in purchase behavior between lower and higher income households. Compared with higher income families’ purchases, foods and beverages purchased by lower income families tend to be higher in calories, fat and sodium content on average.

“Because lower-income families tend to buy more sugary soft drinks than higher income families, they would more readily reap the health benefits of reduced sugary beverage intake,” Zhen says. “However, they would also pay more in beverage taxes, making it a regressive tax.”

Source: RTI International