Participants [in this study] were randomly given either a small bowl or a large one, and a small or large serving spoon. Each participant then spooned out some ice cream. As the participants filled out a survey asking how much they believed they had portioned out for themselves, the researchers weighed their bowls. The results? The participants using the larger bowl ate just over 30% more than those who used the smaller bowl. And despite the fact that they helped themselves to a significantly larger serving size, they didn't think they dished out any more than the others.

Interestingly, the participants who used the large serving spoon got more ice cream, too -- around 15% more than the others -- even if they used the small bowl. Less surprisingly, those who were given both the large bowl and the large spoon ate a whopping 57% more ice cream than those with the smaller bowl and spoon. These results lead to researchers to identify the dishes and serving spoons as "consumption cues."