Plate Size and Color Suggestibility: The Delboeuf Illusion’s Bias on Serving and Eating Behavior
Koert van Ittersum
University of Groningen
August 26, 2011
Journal of Consumer Research, Forthcoming
Despite the challenged contention that consumers serve more onto larger dinnerware, it remains unclear what would cause this and who might be most at risk. The results of five studies suggest that the often overlooked Delboeuf illusion may explain how the size of dinnerware creates two opposing biases that lead people to overserve on larger plates and bowls and underserve on smaller ones. A counter-cyclical sinus-shaped relationship is shown to exist between these serving biases and relative gap between the edges of the food and the dinnerware. Although these serving biases are difficult to eliminate with attention and education, changing the color of one’s dinnerware or table cloth may help attenuate them. By showing the Delboeuf illusion offers a mechanistic explanation for how dinnerware biases serving and intake, we open new theoretical opportunities for linking illusions to eating behavior and suggest how simple changes in design can improve consumer welfare.
Number of Pages in PDF File: 38
Date posted: August 26, 2011