Most people make upwards of 250 food-related decisions a day. Sound high? That's because researchers believe the majority of these decisions are made unconsciously, and that many of our eating habits are actually driven by subtle environmental cues. How we manipulate these cues can have a huge impact on our eating habits.

There are two things to take away from this. The first is that if you're trying to eat right, research suggests that good intentions and willpower alone may not be enough to help you achieve your goals, because unrecognized environmental cues could be sabotaging your efforts. The second is that by recognizing these cues, you can make simple changes to your eating environment that could help you eat healthier without even knowing it. As psychologist Brian Wansink puts it, "the best diet is the one you don't know you're on."

Wansink is what is known as a consumer psychologist. He's the head of Cornell University's Food and Brand Lab, where he has spent close to two decades identifying subtle environmental cues and figuring out not just how they beget unhealthy eating habits, but how they can be tweaked to encourage healthier ones; he's a former Executive Director of the USDA's Center for Nutrition Policy and Promotion; his studies are responsible for the development of the 100 Calorie Pack and the Small Plate Movement.


Dr. Kelly Brownell, Director of The Rudd Center for Obesity at Yale University, has called Wansink "The Sherlock Holmes of Food." And for good reason. Since its creation in 1992, Wansink's Food and Brand Lab has brought humanity's scientific understanding of its relationship with food and food-eating to entirely new levels, all by examining subtle, psychological, environmental cues.

So what kind of environmental cues are we talking about?
Soundbites like the these will probably sound familiar: the food labels on the snacks you buy can have unintended effects on your caloric intake (this study, for example, showed that low-fat labels lead people to eat 16-23% more calories); children who are given cash (rather than a debit card) to purchase school lunches are more likely to purchase healthier food; even when we don't care for the food we're eating, if it's served out of a large container we're liable to eat too much of it. But what makes Wansink's research so unique is that, like all good science, it tends to ask why it's getting certain results.


To give you a sense of what we're talking about here's an example of how Wansink's research has revealed our susceptibility to well-known optical illusions, and how they still manage trick us into consuming more than we need to.

Take a look at the first exercise in this video. The tall-skinny-glass versus short-fat-glass optical illusion is one that most of us, as adults, are familiar with. The mistake that the little girl makes in this video is therefore one that, again, thanks to our experience, we can observe with amusement.

The wonderful thing about optical illusions, however, is that they often manage to dupe us even once we know how they work.

Of course, not everyone likes to be duped by a trick they already know the secret to, especially when money is involved. Consider, for example, The Great Qwest Field Beer Scandal of 2011. Last season, fans of the Seattle Seahawks looking to cheer on their team with a cold brew in hand could shell out $7.25 for a 16oz beer, or $8.50 for 20oz beer.

If you think the people putting down $8.50 were getting more beer for their buck, guess again. As this video clearly demonstrates, both cups actually held 20oz of beer. A statement issued by First & Goal, who manage the stadium for the Seahawks, said that they didn't know how long the cups had been used in the stadium — which tells us it had probably been a while before somebody had thought to pour the contents of one cup into another and realized that they'd been overpaying for beer.

This is all to say that humans aren't the best at perceiving things as seemingly straight forward as glass size. And circumstantial Seahawks evidence aside, Wansink's scientific research supports this.

Various studies conducted by the Cornell Food and Brand Lab have shown, for example, that people pour anywhere between 20 and 40% more liquid into short, wide glasses than they do into tall, skinny ones. These studies even included professional bartenders. "They just don't realize they're doing it," says Wansink, pictured here undoubtedly laughing to himself about the suggestibility of the human mind.

Here's another example of how informed eaters can still be tricked into consuming more than they realize by an optical illusion.

You're all probably familiar with the Delboeuf illusion. Many of you probably even understand how it works. Like the tall/short glass illusion, the Delboeuf illusion is one that plays with our perception of size.

In the version of the illusion that appears here, two black circles of identical size are placed side by side, and surrounded by rings placed at two different distances. If the ring surrounding one circle is closer than the ring surrounding the other, it will result in the former enclosed circle appearing larger than the latter; the more whitespace there is surrounding the object, the smaller it appears.

In this study, Wansink and his colleagues discovered that the same illusion occurs when we use plates and bowls of different sizes. Their findings are described on the Food and Brand Lab website:

Larger plates can make a serving of food appear smaller, and smaller plates can lead us to misjudge that very same quantity of food as being significantly larger. For example, in a study conducted at a health and fitness camp, campers who were given larger bowls served and consumed 16% more cereal than those given smaller bowls.

But what really drove the findings home was the fact that across the test subjects who were eating more food, estimates of how much they had actually consumed were 7% lower than the estimates of the test subjects eating from smaller bowls.

In other words, the researchers found that larger dinnerware could not only cause you to serve more and eat more, it could actually do so while tricking you into believing you'd eaten less — like a culinary equivalent of the Delboeuf illusion.

So now that I know about these deceptive environmental cues, I can just adjust my eating behavior accordingly, right?
Wrong. People suck at overcoming the effects of optical illusions — they're just hardwired into our brains. Fortunately, Wansink's research suggests that you can use these illusions to trick yourself into better eating habits, but probably not by modifying your eating behavior.

A much more straightforward solution, says Wansink, is to just modify your surroundings. Instead of simply being mindful of visual eating cues — like the shape of your glasses and the size of your plates and bowls — Wansink and his colleagues argue that actually replacing your dinnerware (i.e. physically manipulating your eating environment) is a much better solution.

The researchers' findings suggest that having a set of smaller dishes for less healthy items, and sparing the larger dinnerware for healthier fare, can help you consume food in healthier proportions. What's more, the dishes are doing the work for you, allowing you to eat better as "mindlessly," as Wansink would say, as you did before you modified your food environment.

According to Wansink, these strategies are far more likely to succeed than changing your behavior alone. Like he says, "It's easier to change your environment than to change your mind."

Visit the Cornell University Food and Brand Lab