The students walk into Duke University’s version of Panda Express to place a lunch order. They are asked if they would like to downsize their order. A third take the offer. Then, calorie counts go up on the menu, and the researchers repeat the offer to see if more information about their meals encourages students to eat healthier. Again, a third downsize their meals. Even with calorie counts on display, people didn’t change their order.
The federal government is rolling out its calorie counting regulations as part of the new health care reform law. But their effectiveness isn’t firmly established. As Dan Ariely, who conducted the above study at Duke University and wrote The Upside of Irrationality, explained to NPR, the problem is that the calorie count just doesn’t seem to make a big difference in people’s decision making. When we roll into Panda Express or McDonald’s, many of us have already made up our minds.
No matter how much people give you to eat, you’ll eat the whole thing. 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.
Some public health experts—Kelly Brownell, of Yale’s Rudd Center for Food Policy and Obesity, for example—suggest a solution with optimal defaults, wherein “good” behaviors are encouraged and become almost automatic.
Take the case of organ donation. In countries where the default is consenting to donate your organs (blue bars in the chart below), a much higher percentage of people donate. Where people have to explicitly consent (red bars), many fewer people opt in.
In the case of organ donation, how you set the default makes a big difference in the result. But as the Duke study shows, providing calorie counting alone seems to be too gentle a nudge to get people to make different eating decisions.
If we’re serious about addressing obesity, perhaps people need a shove towards downsized portions instead. The Duke study suggests that we’ll downsize when offered an incentive—a financial discount—for doing so. Now, the question is how do we go about mandating better default options or providing those incentives, especially if that compromises the profit margins that come with supersized portions?
Chart via “Personal Responsibility And Obesity: A Constructive Approach To A Controversial Issue” Health Affairs: 2010 (PDF), using data from “Do Defaults Save Lives?” Science: 2003.
