Shifting the goalposts

First they said that fast food was bad because people underestimated the calories in it and so were deceived. Imperfect information meant market failure. Penn & Teller showed that was wrong; so too has Dan Ariely. And, worse, Ariely notes that when folks were presented with the accurate calorie count, they sometimes ate more as they'd previously overestimated things.

Me, I'd then say that there's no market failure and folks ought to be left to make their own choices. I'd have been pretty skeptical about market failure based on imperfect or asymmetric information in the first place as calorie information isn't hard to come by for folks who want it, but these findings show that, even if you thought there was a potential market failure of this sort, it didn't hold in the real world.

But it turns out that giving people accurate information and letting them make informed choices wasn't really the goal. Instead, it's back to the drawing board to find new ways to encourage people to reduce food intake.

Ariely says Duke University also conducted a similar study. He says they posted caloric labels at "the Duke version of Panda Express," a fast-food version of Chinese food. And they saw "absolutely no difference" in caloric consumption.

But then they took it a step further and said: "What else could we do? What other inventions?"

They decided to give people an option of receiving less of the main dish — for example, the orange chicken. People said, "No," according to Ariely. So then they asked people if they wanted less of the side dish. They asked people, "What about we give you half a portion of fries — that would save you 250 calories. Are you interested in that?" Ariely says that more than 40 percent of the people said, "Yes."

"What happened in eating is that no matter how much people give you to eat, you'll eat the whole thing," Ariely says. "So it's really a question of how much you start with. Because we've also tested this — we looked at what people end up with and how much they throw away. People eat everything you give them. But if you give people a mechanism to limit what they're going to have for food later on, people actually eat less as a consequence."

Ariely concludes that offering a smaller portion of the "secondary event" is more successful than trying to reduce the "main event."

"It cuts calories and lets people execute something that's good for them," he says.

But Ariely noticed something surprising. When they stopped the promotion and studied what happened the next day, they found that people did not keep asking for it. They did not say, "Hey, I was here yesterday, they offered me a half a portion of fries, can I do it again?"

"When you offer it [to] people, they understand it's a good offer and they cut down on the calories," Ariely says. "But when you don't offer it to people, they're not doing it for their own self. So we have to think about not just what information we give to people, but how we get them to think about different paths of saving caloric consumption."

Or, maybe the experimented with the new option, found they were still hungry, and wanted the larger portions.

Clearly it's time that New York City implemented a regulation mandating the offering of half-sized portions. Who knows. It might work. And the costs are only born by restaurants rather than by the city or state during times of fiscal restraint.