Objective: Vision is one of a number of factors influencing the amount of food consumed during a meal. The purpose of this study was to investigate the impact of vision on the microstructure of the eating behavior of obese subjects.
Research methods and procedures: Eighteen obese subjects with a body mass index (mean +/- SD) of 39.1 +/- 6.3 kg/m(2) twice consumed a standardized test meal in excess, once with and once without a blindfold. The microstructure of the eating behavior was registered by VIKTOR, a computerized eating monitor. Subjective motivation to eat (i.e., desire to eat, hunger, satiety, and prospective consumption) was rated by visual analogue scales (VASs) before, immediately after, and then hourly up to 3 hours after the test meals.
Results: The obese subjects ate 24% less food when blindfolded (359 +/- 194 g vs. 472 +/- 179 g; p < 0.01). Despite a smaller amount of food consumed when blindfolded, there were no significant differences with or without the blindfold for any of the VASs measuring subjective motivation to eat after test meals.
Discussion: The importance of vision in regulating our eating behavior was demonstrated in this study. The obese subjects ate 24% less food blindfolded without feeling less full. Eating blindfolded could be tested as a didactic tool to make obese subjects aware of what factors affect the termination of eating.