• What would a soda ban have accomplished

    I’ve discussed the potential soda ban in NYC repeatedly. One of my main concerns was that it would not have accomplished its main goal – reduced overall calorie consumption. But there’s new evidence that it may not have even accomplished a simple goal – reduced soda consumption. “Regulating the Way to Obesity: Unintended Consequences of Limiting Sugary Drink Sizes“:

    Objectives: We examined whether a sugary drink limit would still be effective if larger-sized drinks were converted into bundles of smaller-sized drinks.

    Methods: In a behavioral simulation, participants were offered varying food and drink menus. One menu offered 16 oz, 24 oz, or 32 oz drinks for sale. A second menu offered 16 oz drinks, a bundle of two 12 oz drinks, or a bundle of two 16 oz drinks. A third menu offered only 16 oz drinks for sale. The method involved repeated elicitation of choices, and the instructions did not mention a limit on drink size.

    Yes, this is a simulation, but it’s worth considering. The researchers had two menus. On one, you could get any size soda you liked. On the second, the size topped out at 16 ounces, but you could buy more in “bundles” of either two 12 ounce drinks or two 16 ounce drinks. What did they find?

    People bought more soda from the “bundled” menu than from the completely unregulated menu.

    I have no idea if the soda ban would have worked. I was always skeptical. This study, however, raises the possibility that it might have backfired, though, if it had gone through as planned. There was a clear loophole for businesses to sell bundles of smaller sodas together. It turns out that may have led to more soda consumption under the ban, not less.


    • Not particularly surprising! I seem to recall seeing summaries of studies in popular fitness mags which suggested that, when given things like “100 calorie” packs of cookies, etc, folks actually consumed more product than when just given a bag of the stuff!

      But at least those 100 calorie packs cost more and come with extra (probably non-biodegradable) packaging!

    • Very interesting. This of course corroborates the traditional understanding that big sizes spur consumption (since there was a lot more consumption under the “unregulated” conditions than when only 16-oz sizes were sold), but implies that bundling can accomplish the same task, possibly even more effectively. (Though possibly less if they actually gave out the sodas and made the participants aware they’d have to carry them elsewhere before drinking, which inconvenience factor the researchers nod to.)

    • My first day on the job at a fast food place, the owner drilled into me that cups were a huge cost and not to ever give away the good cups for water, etc. So it’s unlikely that restaurants would do a bundle in reality.

      That said, I’d most like to see how effective a policy could be that required the default soda size for a combo meal to be 16 oz or less. That doesn’t impinge on anyone’s freedom of choice, but simply makes it easier to just get the smaller size.

    • I do wish that there had been a third group that included both menus. From their study design, it isn’t clear whether the effect was due to the fact that the second menu prohibited drink sizes over 16 ounces, or the fact that the first menu prohibited bundles of drinks. They really needed a control group offering both the bundled drinks and the larger sized drinks.