Another study raises questions about sweetened beverage taxes

A small group of food and agricultural economists have been quietly releasing research that questions the argument that sweetened beverage taxes will have any meaningful impact on the rates of obesity.  First was a French study showing fat taxes to be quite regressive (i.e., the burden is most heavily paid by the poor) having very small effects on nutritional content.  Then was a UC Davis study showing that the only kind of tax to have much effect on weight would be an across-the-board food or calorie tax.  After that, I discussed a Cornell study showing that sweetened beverage taxes are likely to be far less effective than previously predicted if food taxes are only calculated at the register and not posted on the shelf (as is the case in virtually all US retail outlets).  I then talked about my own research on the issue, pointing out some weaknesses in much of the conceptual reasoning about fat taxes. 

Now, comes this paper just accepted for publication in the American Journal of Agricultural Economics.   The authors find: 

A half-cent per ounce increase in sugar-sweetened beverage prices is predicted to reduce total calories from the 23 foods and beverages but increase sodium and fat intakes as a result of product substitution.

The authors also showed that previous studies, which failed to account for the full substitution effects across foods (an issue we highlighted back in 2008 in this paper), would over-estimate the effectiveness of a sweetened beverage tax.  They also estimate that the consumer welfare losses that results from paying higher prices from a tax are higher among the poorer consumers than the richer consumers.  

Ultimately, the authors predict that a one-half cent tax per once of sweetened beverages would cause

reductions of 0.37 and 0.16 kg/person in 1 year

for low and high income consumers.