Putting Soda Taxes to the Test

soda-consumptionIt’s time for a vote, apparently. And the vote is not just about Trump and Clinton. We’re voting on a soda tax in four cities today: Boulder, CO, and Oakland, San Francisco, and Albany, CA. This question has turned into a stupid food fight, in our humble opinion. We’re talking about soda taxes, not the presidential and congressional elections.

Soda is in decline. The decline of soda is not solving the problem of excess obesity. And it will not.

People with deep convictions (dare we mention bias?) favoring soda taxes are publishing a steady stream of studies to prove that if you tax soda, the cost will go up and consumption will go down. Arguing the nuances is pointless. Economists settled this question long ago. When prices go up, demand goes down.

Jumping from that point, the advocates issue a dizzying array of models to describe the wonderful benefits of a soda tax. PLOS Medicine has a new one that tells us Mexico will save close to a billion dollars and save 18,900 lives because of their soda tax. We hope it’s true.

Alas, we don’t know.

Consumer behavior is a complex mystery. When people stop consuming one thing, they start consuming others. Right now Americans are consuming less soda than they’ve consumed since the 1980s. But we’re consuming a whole bunch more pumpkin spice latte. And sweet tea. Wine is doing quite well, too. The options are too many to count. Have a smoothie! It’s healthy!

Beyond the certainty that people will consume other things in place of soda, we have the uncertainty of how much impact drinking less soda will actually have on obesity and related diseases. In all these tidy models, we can assume that the associations between soda and obesity are causal. In the real world, we simply don’t know.

A likely outcome of soda tax fights is disappointment. People will drink even less soda. Governments will collect some tax revenue. Obesity rates will remain stubbornly high.

The assault on soda for a decade and a half has not moved the needle discernibly. More of the same is unlikely to have a greater effect.

We hope and pray for greater curiosity about this disease. We need more emphasis on probative research and creative problem solving. Another decade of fighting about taxing a beverage in decline would be a profound waste of time.

Click here for a more positive view on the benefits of taxing soda. Click here and here for more on the soda tax votes. For a fearless declaration from the Huffington Post that “Science Says Yes” on soda taxes, click here.

Vote, photograph © John Schneider / flickr

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November 8, 2016

4 Responses to “Putting Soda Taxes to the Test”

  1. November 08, 2016 at 6:33 am, Joe Gitchell said:

    Ah, sweet simplicity–so delicious and yet so frequently unsatisfying. A la HL Mencken on complex problems, I’d say….

    Thanks, Ted.


    • November 08, 2016 at 7:45 am, Ted said:

      I’m with Julian Simcox: “Enough with the policy-based evidence.”

  2. November 08, 2016 at 7:47 am, Pam Schu said:

    Thank you for highlighting curiosity about the disease and creative problem solving. Both require an open mind and an awareness of our own personal biases. And the best part, these attributes add enjoyment and meaning to the work we do.

  3. November 08, 2016 at 7:56 am, Susan Burke March said:

    Another good piece in the Economist says, “Taxes also work better if they distinguish between different degrees of sugariness. Hungary’s tax, which also applies to salt and fat, varies according to the amount of offending ingredient used. A review of the policy found that 40% of manufacturers had adjusted their recipes accordingly.”