Erica C. Barnett (via Marion Nestle) points to a fascinating new study from the USDA on the effects of taxing sweetened beverages. The flagship chart sums things up nicely:

USDA ERS caloric tax

[Larger version here.]

What’s more, the study finds that even the relatively modest reductions in calorie intake from sweetened beverages would put a noticeable dent in our waistlines:

  • By assuming that 1 pound of body fat has about 3,500 calories, and assuming all else remains equal, the daily calorie reductions would translate into an average reduction of 3.8 pounds over a year for adults and 4.5 pounds over a year for children.
  • The weight loss induced by the tax could reduce the overweight prevalence among adults from 66.9 to 62.4 percent and the prevalence of obesity from 33.4 to 30.4 percent. For children, the at-risk-of-overweight prevalence would decline from 32.2 to 27.0 percent and the overweight prevalence would decline from 16.6 to 13.7 percent.

While it’s not as if a 20 percent surcharge on soda would solve the nation’s obesity problem, neither is it the case that prices don’t make a real difference. So to the extent that weight gain is a serious problem for public health, it seems that prices may play an important role in solving it.

Personally, I’d love to see some revenue-neutral version of a steep Pigovian tax on sugary products. The revenue could be easily redirected toward uses that would boost equity, such as a tax rebate for low-income individuals, or a general sales tax reduction, or perhaps even funding for health programs. There’s no real public benefit to cheap empty calories, and an abundance of ways to lend a financial helping hand where it’s needed.

Image is from Economic Research Service report summary, “Taxing Caloric Sweetened Beverages,” July 2010, here.