Soda Tax To Combat Obesity, Will it Work?

Cigarettes are taxed, alcohol is taxed, why aren't soft drinks taxed?

One huge reason for the dirth of legislation levied against unhealthy foods including sodas is the enormous lobby of the food industry in DC and across the country. Whenever there is serious consideration of restricting access to unhealthy foods (such as in public schools) there is enormous resistance. Big Food has lots of money to manipulate (I mean influence) public opinion so that there is not enough momentum and public support for anti-junk food policies. The sad story is that public health professionals can have nearly the same trouble improving access to healthy, nutritious foods in these same places!!

The lead story of the Business section of today's New York Times was "Tempest in a Soda Bottle: Proposed Tax on Sugary Beverages Debated." It discusses the increased political open-mindedness to the idea of a tax on soft drinks and sugar-sweetened beverages in the US and the likely resistance to such a proposal.

Here's why I think this could be a good idea.

Sugar-sweetened beverages comprise nearly 10% of the calories consumed by adults and children in the United States. If we want Americans to eat fewer calories, reducing consumption of sugar-sweetened beverages is an easy way to do it, without sacrificing nutrient intake.

This assumes that a soda tax will reduce consumption. Is there evidence for that? Yes. Unfortunately, most of the evidence comes from taxes levied in other industries and due to differences in elasticity (how price may affect demand) there are only rough estimates.

Authors of the New England Journal of Medicine article that prompted the New York Times to run this lead story, states that

"Currently, 33 states have sales taxes on soft drinks (mean rate 5.2%) but the taxes are too small to affect consumption and the revenues are not earmarked for programs related to health."

This indicates that a) a soda tax by itself will have only moderate impact on consumption, and b) what we do with that tax revenue will be critical in determining whether we really make an impact on preventing or reducing obesity in this country.

The study authors estimate that a tax of 1 cent per fluid ounce would increase the cost of a 20-oz soda (a typical plastic bottle size nowadays) by 15-20%. This could lead to a reduction in 10% of the calories consumed by a person per day! It may not sound like a lot, but it would be a huge population impact.

Interestingly, the authors only propose this tax on beverages containing calorie-adding sweeteners, like sugar and high-fructose corn syrup, thus excluding diet sodas from their tax. They claim such a tax "may promote the consumption of no-calorie beverages, most notably, water." Yet, fail to discuss the implications of people that switch from regular soda to diet and what effect (if any) that would have on obesity control efforts.

If the money is put to good use, improving nutrition in our schools and reviving physical education classes, then I would be quite pleased. Obama appears interested in getting more information about this strategy for obesity prevention. I'd bet DHHS Secretary Sebelius has been briefed already. Could it pass the Congress? hmmm... I guess that's what public health communication is for!