Less Color, Less Craving: The Impact of Food Image Desaturation on Appetite and Motivation

Background Color is a dominant determinant of food perception and appetite. Highly saturated images enhance perceived palatability and motivational salience, yet the behavioral consequences of reducing color saturation remain unclear. Objective This study investigated how desaturation of food images influences appetite, hedonic evaluation, and approach motivation. Methods A total of 120 healthy adults (60 females, 60 males; mean age = 24.7 ± 3.9 years) participated in a within-subjects experiment. Participants viewed 80 standardized food images (40 high-calorie, 40 low-calorie) presented in both full-color and desaturated (grayscale) formats. After each image, participants rated visual appeal, desire to eat, and expected tastiness on 9-point Likert scales, followed by a 5-second keypress task indexing motivational effort. Data were analyzed using repeated-measures ANOVAs and mixed-effects models. Results Color significantly increased appetite (Mcolor = 6.60, Mgrayscale = 5.06, F (1,119) = 162.84, p  < .001, η²ₚ=.58) and motivational effort (15.56 vs. 10.06 keypresses, F (1,119) = 128.37, p  < .001, η²ₚ=.52). High-calorie foods elicited stronger appetitive and motivational responses overall ( F (1,119) = 173.41, p  < .001, η²ₚ=.59). Restrained eating moderated these effects (interaction b  = − 0.27, p  = .001), indicating that individuals with higher cognitive restraint showed attenuated color sensitivity. Conclusions Reducing color saturation in food imagery markedly diminishes appetite and motivation, especially toward high-calorie foods. These findings underscore the critical role of visual vividness in appetitive processing and suggest that desaturation may serve as an unobtrusive visual intervention for craving control in digital food environments.