You might think that how and what you choose to eat is more or less determined by hunger, your particular craving for the moment and, quite likely, your blood sugar level. Research now shows that it's a bit more nuanced than that. Brian Wansink, leading researcher on eating behavior at Cornell University, has published some interesting facts in his book Slim by Design and more recently in an article in New Scientist magazine. Through a number of experiments, he shows how our eating environment influences our eating behavior in ways we might not expect.
For example, we serve ourselves larger portions if the plate is of the same color as the food. One experiment let random participants have pasta with tomato sauce on red or white plates, respectively. Other participants had pasta with white sauce on red or white plates, respectively. The conclusion of this experiment was that people whose food matched the color of the plate had 18% larger portions than the people whose food color was in contrast to the color of their plates.
The result of the next experiment is perhaps a bit more expected. If you eat on a smaller plate, you tend to serve yourself a smaller portion. Eating on a 25 cm plate as opposed to a 30 cm plate resulted in having a 22% smaller serving.
Wansink also studied people in their New York homes. Some families served the food on the table, while other families left the food in pans and pots on the stove and let their family members serve themselves from there. This latter group had 19% less food than the families who put the food on the table. However, serving food on the table, but changing from a bigger to a smaller ladle, led to people eating 14% less food than when using their regular ladle.
And here is something for me, who pretty much hates salad: serving salad in a centrally placed bowl on the table, or giving family members a separate small plate, solely for salad, led to people having more salad than they otherwise would.
People's wine drinking behavior were also studied. Or rather, their wine pouring behavior. This is amusing, because wine drinkers are apparently just like kids: people who were given a narrow, tall wine glass poured on average 12% less wine than people with wide, lower glasses. Like kids with soda, people judged the amount of wine by how high the liquid rose inside the glass instead of by its actual volume. Also, pouring wine in a glass from a standing position made people pour 12% less wine than if they were sitting down, looking at the glass from the side. It seems this is due to the fact that a glass looks more full when observed from above and that the test subjects were afraid that the wine would run over.
Wansink and his team also visited some thirty restaurants all over the US. They made drawings of planning, window and table placement, how close the tables were to the bar and the kitchen etc. For between a few weeks to a few months they observed what was ordered from the different tables. It turned out that diners tended to order healthier food if they were sitting by a window or in a well-lit part of the restaurant. Those who sat at the longest distance from the entrance ordered less salad and they had dessert 73% more often than the other guests. Groups of people of more than four people who sat within two tables' distance from the bar had on average three beers or cocktails more than those who sat further away from the bar. People who could see a TV screen from their table, and were most likely focusing their attention on it, had more fried food than the other guests.
There are some interesting lessons to be learned from these findings, and if nothing else, they make a pretty good conversation starter!