Mind Over Platter

Brian Wansink’s experiments show all the ways we can be lulled—or lulled—into overeating. ways we can be lulled into overeating.

September/October 2007

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Mind Over Platter


In the past half-century, Americans have become the world's premier multitaskers: a shave-while-commuting, eat-on-the-go people. It's been great for our productivity, but hazardous to our waistlines. Roughly 65 percent of Americans are now overweight or obese, according to the National Center for Health Statistics, and the number is rising. And not, Brian Wansink wants to make clear, for the reasons you might expect.

“Most people think they overeat because the food's really, really good, or they're really, really hungry,” says Wansink, PhD '91. “Wrong.” Recipes and appetites are convenient excuses, scapegoats for the much more insidious eating cues that have come to pervade our world and define the American eating experience.

A simple experiment: go to your cabinet. Choose one taller, skinnier glass (a white wine glass, say) and one shorter, wider one (for red wine, maybe). Now try to pour the same amount of liquid into each. Unless you're exceptional, or are in on the trick, you poured a third more liquid into the shorter, wider glass. That's because our minds tend to emphasize the vertical over the horizontal, and it's just one of the many psychological cues that cause caloric overindulgence.

Wansink, a professor of marketing at Cornell University, is an expert in the ways we delude ourselves into eating more than we ought. And that's why he came up with Consumer Camp. The event is a daylong, hands- and mouths-on showcase of his research into “The Science of Snacking.” Now in its eighth year, the camp takes place each April in Cornell's Food and Brand Lab.

I go to the gym regularly and have an abnormally dull sweet tooth, so I didn't expect to fit the average profile of a Consumer Camp attendee. I imagined desperate dieters and devoted fans of Wansink's book, Mindless Eating: Why We Eat More Than We Think (Bantam Books). I was wrong. The participants were diverse, but most were slim and fit. They included a smattering of journalists, including a Good Morning America film crew, a few public health officials and a number of everyday citizens just hoping to learn why we eat more M&Ms when they're sorted by color.

On my way into Warren Hall to join their ranks, I bumped into Wansink. He was a ball of energy. The GMA crew was setting up in the hallway outside his lab, and the camp's breakfast reception had just begun; he was juggling multiple tasks. He directed me toward the reception area, telling me to look for the room marker, a purple balloon. Wansink, it was obvious, nurtures a healthy appreciation for irony: the balloon was weighted down by an 8-ounce bag of Mini Oreos.

Wansink, with his high brow, rimless glasses and mischievous smirk, looks a little like a high school chemistry teacher, someone well-equipped to tolerate teenagers. His gee-golly manner subverts staidness with a mix of good-natured unconventionality and optimism. He lowers his voice when he swears and chuckles readily.

Wansink grew up in Sioux City, Iowa, where life revolved around agriculture. His immediate family lived in town, but most of his other relatives worked on farms outside the city, and he spent his summers selling tomatoes door-to-door and detasseling corn. “When you got older,” he told me, “you'd do something else food-related, like deliver pizza. Everything was food-related.” When Wansink left the Midwest, to seek a PhD in marketing at the Graduate School of Business, he took with him this alimentary view of life. Where the Stanford application asked for his research interests, he wrote, “My goal is to get people to eat more fruits and vegetables.”

Wansink told me that he struggled to get through Stanford. “It was only by some miracle that I got into the University,” he said, “and only by a second miracle that I ended up graduating.” His research into “situation-specific attitudes toward food” didn't fit easily into a marketing framework. “People said, you will never get a job; that's a stupid dissertation,” he said.

His dissertation adviser, marketing professor Michael Ray, has a different story. “He may have felt that way,” he said of Wansink's sense of inadequacy. “But he gives me more credit for helping him through the program than I think I deserve.” After a string of effusive compliments about Wansink, Ray grew self-conscious, and added, “You get the idea that this is one of my favorite people.” Wansink often worked with other departments—communications, psychology and such. When he inevitably had to leave a project, people would ask Ray to recommend new hires; “We want a Brian Wansink type,” they'd tell him.

Wansink won the Marketing Science Institute's award for best dissertation in 1989 and then led the peripatetic life of unestablished academic for a few years, jumping from posts at Dartmouth, in Amsterdam, at Wharton, and finally to the University of Illinois in 1997. There he established the Food and Brand Lab to focus on the psychology of food and eating. Cornell wooed him—and the lab—to Ithaca in 2003.

The Food and Brand Lab is essentially two rooms attached to Wansink's office by one-way mirrors, with hidden scales and cameras that record participants' eating behaviors. “Within about three hours, we can transform both rooms to look like pretty much any room in your house,” Wansink says. Wainscoting and rugs come and go. A household's worth of furniture is stored downstairs. Lighting styles change. A hidden wall compartment opens to reveal a big-screen TV.

The lab is also a network of restaurants, bars, cafeterias, school lunchrooms and households that allow Wansink to test his ideas in real-world settings. “We spend probably at least half our time out in the field getting dirty, counting the chicken bones that people throw away at sports bars or weighing popcorn containers in theaters.”

His inventiveness is one of his key contributions to the field. When I asked Barbara Rolls, a nutrition professor at Penn State, about Wansink, she laughed and said, “He's a wild man! He's got so much energy.” Rolls also has studied issues like the effect of plate size on food intake. “We do very controlled lab studies,” she said, “and he's out in the field usually. He's a good addition to our field because he comes from a marketing background and a lot of the issues that he understands are not the kinds of things that we would even think of.”

The bulk of Wansink's experiments focus on how our minds unconsciously process cues to make us eat more or eat less. His research tells us something about the way our brains work, about how we interpret our environment and unconsciously make decisions that can profoundly influence our lives. It strives to explain our national propensity to overconsume, a factor in the $35-billion-a-year dieting industry. Perhaps more than anything, though, Wansink's research fascinates so many—including the producers of 20/20, on which he has made several appearances, and Oprah Winfrey, who featured his book in her magazine—because he approaches it in splashy, unconventional ways.

Take the popcorn study. Several of Wansink's studies have proved that delivery containers—plates, bowls, buckets, etc.—affect how much we eat to an extraordinary degree. Large plates, for instance, make portions look smaller (size matters), while the miniature Snickers in an opaque candy jar are less tempting than those in a clear one (exposure matters). Wansink wanted to test this idea with popcorn buckets. More specifically, he wanted to test the counterintuitive notion that the size of the bucket could overpower more fundamental factors like food quality or hunger level.

Wansink designed a study that eliminated nearly every variable except bucket size. He gave his study participants a huge lunch, to ensure they wouldn't be hungry. Then he took them all to an Adam Sandler movie and gave them free, all-you-can-eat popcorn. Some got medium-sized buckets, and others jumbo buckets—the kind that might cost $7 in a San Francisco theater. But—and here's the trick—the popcorn was disgusting. Five days old, and staler than 1970s fashion trends. The least discerning squirrel in the world would turn up its nose. So now he's got people who aren't hungry, and have week-old popcorn. And what happens? The people with larger buckets still eat up to 34 percent more.

And Wansink took delight in pointing this out to them. When he asked them how they liked the popcorn, they told him, “Oh, God, that was just terrible! That was rancid! How could you give that to me?” Then he pointed out that they ate half again as much as those with smaller buckets.

“They're totally speechless,” he recalls. “And it's really fun to hear them go, 'Well, uh, I didn't have breakfast, that's it.' They're stretching for an answer, but the last thing they're willing to acknowledge is that this external cue”—the size of the bucket—“influenced them.”

One criticism often lobbed at Wansink and his research is that of trickery. Study participants like to boast that, having been fooled once, they'll be wiser in the future. To counter these claims, he stacks the cards against himself. To prove that we pour more liquid into a shorter, wider glass than a tall, skinny one, for instance, he tested professional bartenders in Philadelphia, who averaged 6.3 years behind the counter. If any group of individuals knew what a 1.5-ounce shot should look like, it was these guys.

They failed miserably. On average, they poured 20.5 percent more alcohol into a short, wide glass than a tall, skinny one, all the while confident that they were pouring equal-sized shots. When the bartenders cried foul, Wansink let them take the test again after he'd told them the results. They still poured more in the smaller glass.

Wansink spent the first hour of Consumer Camp discussing his findings in an auditorium festooned with posters that advertise his research. “Why Don't French Women Get Fat? Internal and External Cues of Meal Cessation” quickly became my favorite. He played footage from the lab in which hidden cameras observed as unknowing participants slurped soup from a bowl designed to refill itself. After being told all about his joy in secretly testing friends at Super Bowl parties, grad students in seminars, and friends over for dinner, we campers began to get a little nervous. “I feel like everything's a test,” a journalist from Syracuse whispered to me as she declined a cup of coffee during a break.

Around 10 a.m., we were led to an ad hoc laboratory. Wansink planned to make us into lab rats—albeit rats with some knowledge of the maze: after all, we had just learned about the skinny-glass gambit and the pretzel-bowl stratagem. Tables around the room were laid with assorted glasses, bowls, bottles and plates, and cheery undergraduate assistants stood at each.

When I got to the front of the line at my first station, a pretty undergraduate researcher presented me with four plates. Two were meals of steak and asparagus; she asked me to form a split-second decision on which I'd rather eat. They looked identical to me, so I just pointed at one. The next two plates had fried chicken and brussels sprouts—same routine.

Subsequent stations required us to pour a like amount of water into (you guessed it) differently shaped glasses, or to scoop pretzels onto differently sized plates. At some stations, although few of us noticed at the time, an assistant held out a sample glass to demonstrate what we were to do—a subconscious suggestion to affect the size of our pour.

Afterward, we learned that even a group of newly wised-up consumers, skeptical journalists, and public health experts proved susceptible to the subliminal cues of Wansink & Co. People who glimpsed a full glass of juice before they poured their own took almost 30 percent more juice than those who saw a half-full glass.

And the plates? One of Wansink's undergraduates, Becky Vayo, whose career aspiration is to host a cooking show, had hypothesized that the right side of our brain, which is more emotional and regulates the left half of our body, would exaggerate our distaste for items on the left side of the plate (and vice versa). She was right: most people preferred the dishes where the unpopular asparagus or brussels sprouts occupied the right side of the plate.

To our relief, the lunch table proffered no plates, no bowls, no glasses (tall, skinny or dribble) but box lunches and cans of diet soda in ice. I sat down with my turkey sandwich, apple and chips and ate. I even got a little toy rhinoceros in my lunchbox, which delighted me to an embarrassing degree.

Afterward we were ushered outside for a stroll around Beebee Lake. As soon as we arose from our seats, the lab assistants swarmed over our half-eaten meals—notebooks and scales in hand. They weighed what we'd left behind, counted the number of uneaten chips, and asked us to rate our satisfaction with the meal on the way out. We had been like turkeys in the week before Thanksgiving, easily assuaged even while the farmer was sharpening the axe.

Wansink revealed that the exercise was a preliminary experiment on behalf of Boeing, the airplane manufacturer. Boeing had asked Wansink to help brainstorm ways to increase passengers' satisfaction with their in-flight meals—generally considered the real-world equivalent of five-day-old popcorn.

Wansink had included “worthless, two- or three-cent toys” in about half the lunchboxes—my rhinoceros was one of them—on the theory that pleasant surprises, even tiny ones, increase satisfaction. He was wildly right. After we finished our meals but before we knew anything about the study, Wansink's assistants handed us a questionnaire that asked how much we'd have been willing to pay for the meal. Those who received a toy said they would have paid $6, while the toyless ones thought the meal worth only $3.50. The toys made us healthier, too—toy-receivers ate slightly fewer chips and more of their apple. The experiment made me think of my parents, who now make it a point to stay in hotels that offer complimentary chocolate chip cookies at the reception desk.

Studies of food psychology aren't aimed only at dieters. Since his Illinois days, Wansink and his lab have worked with retirement centers to help seniors eat healthier. The elderly often take medications that cause appetite loss, so Wansink counters this with small environmental tweaks. Mood lighting and music, he's found, cause diners to linger at the table, meaning they eat more from their plate. Using more exotic, descriptive names for foods—“Bavarian Dark Forest Chocolate Cake” instead of “Chocolate Cake,” for example—make dishes 23 percent more popular. He's done similar work with the U.S. military, which feared that soldiers in combat weren't getting enough calories to maintain a high alert level.

Because these psychological cues have a profound influence on our actions without us even knowing, knowledge of them can be extraordinarily powerful. Wansink says he gets three or four calls a week from Big Food—companies like Nabisco or Coca-Cola—asking him to help design packaging that will get people to eat more. He turns them all down.

He makes an exception for findings that benefit industry and consumers alike. In 1996, when he was an assistant professor at Wharton, Wansink's early research led to an epiphany: if snacks come in smaller packages, most people will eat less of them. The idea so gripped him that he took his car and traveled the country, presenting the information to tables of skeptical executives at Nabisco, Kellogg and other food companies. “I said, 'Look, there's a tremendous opportunity here to help people eat less, and you can probably charge a premium, so you can make a profit.'” He saw it as a win-win. The idea eventually became the popular 100-calorie packs of Oreos, Chips Ahoy!, Cheese Nips and other snack foods. “It was a great step forward,” Wansink says.

Lately Wansink has turned his lab's attention to school cafeterias, a perennial target of nutritional criticism. He hopes that improving the way schoolchildren eat will be his biggest accomplishment. “If 40 years from now you can say, look what hot lunches look like now, and look what they used to be like, and say, wow”—he pauses, looking for words. “I can say I helped change hot lunches rather than say, look at the size of my boat.”

In his own small way, Wansink is working to change the waistline of a nation. Americans are heavier than most other nationalities—because our way of life bombards us with cues to eat more and more. “If you take the typical French person and put him in an American environment, he'll fall victim to the same cues that influence all of us,” he says. “We've got huge pantries and huge refrigerators inside huge kitchens inside huge houses,” Wansink said. “We can store a month's worth of potato chips and ice cream and still have room to spare.” Fittingly, cities with the highest premium on space—New York, for example—also show off the healthiest midsections.

The faster pace of life plays a part, too. American eating habits have become more and more erratic in the past 30 years—just try to think, for instance, which days you ate breakfast last week. “If you have the same bowl of oatmeal every day at the same time and in the same bowl,” Wansink says, “you are going to be less influenced by these cues.”

Wansink's experiments hammer home a bleak point: if the U.S. lifestyle encourages overeating, and if even knowledgeable consumers can be fooled into eating more, what hope is there for chronic snackers? Wansink ended camp with a number of suggestions that basically amount to this: remove the nefarious eating cues in your life. Adopt small plates, skinny wine glasses, opaque candy dishes.

Wansink hosted a small dinner reception at his home after camp let out. His wife, a chef trained at France's Le Cordon Bleu, wasn't cooking—“He gave me the night off,” she said—so we ate pizza. Wansink offered everyone wine, and we couldn't help but notice that he had plenty of short, wide red wine glasses. We asked him why he hadn't removed them.

His expression was wry. “I haven't gone that far yet.”

Read a May 2010 update on this story.

Barrett Sheridan, ’06, is a journalist at Newsweek International. 

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