Late last year, a little book called “Mindless Eating” started appearing in bookstores. It was written by Brian Wansink, a Cornell professor who has spent his career doing brilliantly mischievous experiments about the psychology of eating.
In one of my favorites, Mr. Wansink gave away five-day-old popcorn — “stale enough to squeak when it was eaten,” he wrote — to moviegoers one day at a theater in the Chicago suburbs. The crux of the experiment lay in the size of the buckets that held the popcorn. Some people got merely big buckets, while others received truly enormous ones. Both sizes held more popcorn than a typical person could finish.
Yet when the Wansink research team weighed the buckets after the movie, there was a huge difference in the amounts the two groups ate. Those with the bigger buckets inhaled 53 percent more on average, suggesting that a lot of stale popcorn is somehow more appealing than a little stale popcorn.
Over the years, Mr. Wansink has done similar experiments with everything from different-size dinner plates to bottomless bowls of tomato soup that are secretly connected to a tube underneath a restaurant table. His overarching conclusion is that our decisions about eating often have little to do with how hungry we are. Instead, we rely on cues like the size of a popcorn bucket — or the way we organize our refrigerator — to tell us how much to eat. These cues can add 200 calories a day to our diet, but the only way we’ll notice we are overeating is that our pants will eventually get too tight.
The scariest part is that most of us think we are immune to these hidden persuaders. When the moviegoers were told about the popcorn experiment afterward, most of them scoffed at the idea that their bucket size had any effect on them. “Things like that don’t trick me,” one of the gorgers said.
After reading the first few chapters of “Mindless Eating,” I called Mr. Wansink, an energetic 46-year-old Iowan, to talk about his research. As luck would have it, he said that he was coming to New York a few days later to give a speech. In a flash of masochism, I then asked if he would be willing to stop by my apartment and tell me everything that was wrong with my kitchen.
“That’d be so cool!” he replied.
Toward the end of “Mindless Eating,” there is a short passage making it clear that Mr. Wansink’s work is about far more than just food. “The 19th century has been called the Century of Hygiene,” he writes. “The 20th century was the Century of Medicine.”
This century, he continues, will be the Century of Behavior Change. “Medicine is still making fundamental discoveries that can fight disease, but changing everyday, long-term behavior is the key to adding years and quality to our lives. This will involve reducing risky behavior and making changes in exercise and nutrition. There isn’t a simple prescription that can be written for such behavior change.”
Over the last couple of decades, a new field of economics, behavioral economics, has emerged to explain why people so often act in ways that are contrary to their own interests. They overeat, smoke, forget to take their medicine and don’t save enough for retirement, saying all the while that they wish they could change. Figuring out how to turn these wishes into action could put a dent in some big social problems.
Last year, President Bush signed a new pension law that was based in part on this idea. It gave companies an incentive to sign up workers automatically for 401(k) plans. The workers can still opt out; in fact, they have the same range of choices they have always had. But if they do nothing, a small part of their salary is set aside for retirement.
The pension bill sprang directly from academic research showing that automatic plans vastly increased the amount of money that people saved. “It’s the success of behavioral economics, by far,” Daniel Kahneman, the Nobel Prize-winning psychologist who helped found the field, recently told me.
Whether it’s 401(k)’s or food, the way choices are presented to people — what the economist Richard Thaler calls “choice architecture” — has a huge effect on the decisions they make. As Mr. Wansink and I stood in front of my pantry, he was making the exact same point.
He started off with some praise, which I was perfectly willing to accept. “What all this cues up is food preparation,” he said, pointing to bottles of olive oil and vinegar, sacks of rice and various baking ingredients. “The default when you open a pantry like this isn’t convenience — it’s ‘what are we going to make tonight?’ ”
The worst thing for a pantry, he said, are a lot of snack packages in plain sight that require almost no work to open. Every time you glance at one, it essentially asks you a question: “In the mood for a Dorito right now?” The more often you’re asked the question, the more Doritos you will eat.
Mr. Wansink knows that he runs the risk of sounding like a scold, and he goes out of his way to avoid it. (The book jacket for “Mindless Eating” notes that he “enjoys both French food and French fries each week.”) That’s probably why he began by saying some nice things about my pantry. It went downhill from there.
For one thing, the food in the pantry sits behind glass doors. So every time someone in my family walks into the kitchen, we hear a version of that Doritos question in our minds: “Hungry?” Our inedible plates, on the other hand, are hidden behind wooden cabinet doors.
But those plates have their own problems. Like most American dinner plates, ours are big — almost 12 inches in diameter. “Pretty ample,” as Mr. Wansink said. Fifty years ago, when Americans were a lot skinnier, plates were a lot smaller. Large plates and bowls lead to more eating for the same reason giant popcorn buckets do: they make portions look smaller. Short, wide drinking glasses have a similar effect.
Mr. Wansink and his team were so taken aback by the results of their experiments on the shape of glasses that some of them went home and replaced the squat glasses they owned with tall, skinny ones. Mr. Wansink also uses dinner plates from the 1940s, which have the double advantage of being smaller and being more interesting than your typical Crate and Barrel fare.
Not every one of his ideas, of course, is worth the trade-off. My wife and I are not going to hide all our food. We like looking at our olive oil. But we get no particular joy out of eating off 12-inch plates. So we have started looking at inexpensive antiques as replacements.
The broader point, I think, is that there is no way to avoid the sort of cues that Mr. Wansink describes. We just have to decide which cues we are going to choose — the ones that lead to us eat more or the ones that lead us to eat less. The same goes for retirement savings, among many other things. Once we understand that, we can start using our mindlessness to our advantage.
