The purpose of this study was to determine if an instruction to take fewer bites than typically taken, would reduce intake and overcome the known environmental cue of plate size. In a previous study, fifty-five participants (34F) ate ad libitum macaroni and cheese in groups of four, either from a small plate or a large plate. They ate 111Â±35g with 12Â±4 bites from the small plate, and 195Â±111g with 20Â± 6 bites from the large plate. The current study employed the same paradigm. Sixty participants (33F) were given bite count feedback and were instructed to take only 12 bites, while eating from either a small plate or a large plate. Participants ate 135Â±52g with 12Â±3 bites from the small plate and 177Â±63g with 12Â±2 bites from the large plate. Results of a 2x2 ANOVA indicate a main effect of plate size (p<.001) and instruction (p<.001) on bites taken and an interaction (p<.001). Plate size also affected grams consumed (p<.001). Notably, instruction also affected bite size (p<.001). These results suggest that people will reduce the number of bites when instructed to, but will increase their bite size to compensate for the reduced bite allowance.
Jasper, Phillip W.; Salley, James N.; Hoover, Adam; and Muth, Eric R., "The Effect of a Target Bite Count and Plate Size on Food Intake." (2015). Graduate Research and Discovery Symposium (GRADS). 167.