Earlier research had looked at how the size of plates we eat on determines how much we eat. Larger plates can make a serving of food appear smaller and smaller plates can lead us to misjudge the same quantity of food as being significantly larger. This suggested that not only could large dinnerware cause us to eat more, but it can trick us into believing we have eaten less.
The wine glass study, however, is far more conclusive and interesting. The researchers had recruited 73 volunteers who normally drank at least one glass of wine every week. They were asked to pour themselves a normal serving of wine. What the research clearly showed was that the volunteers unintentionally poured larger servings when their glasses were wider, when they held them in their hands while pouring, and also when the glassware matched the wine. If you want to pour and drink less wine, stick to the narrow wine glasses, and only pour if your glass is on the table or counter, not in your hand. In either case, youll pour about 9-12% less, Wansink said.
The researchers used three different types of wine glasses to test the effect of size and shape: large, wide or standard. When glasses were wider, participants poured 11.9% more wine than the standard glass. In another experiment, the volunteers poured 12.2% more wine when they were holding their glasses while the wine was being poured, compared to pouring it into a glass placed on a table. Finally, to examine the visual effects of colour contrast, the researchers found that when there was low contrast between the glass and the wine (white wine in a clear glass), participants poured 9.2% more wine than when there was high contrast (red wine in a clear glass). So next time you are out for a fancy dinner, ask for the narrow wine glass and send back any oversized plates. It could affect how you feel the next morning.