Cognitive Distraction at Mealtime Decreases Amount Consumed in Healthy Young Adults: A Randomized Crossover Exploratory Study

BACKGROUND: Environmental distractions have been shown to affect eating patterns. OBJECTIVE: The purpose of this study was to determine the effects of a cognitive distraction on amount, preference, and memory of food consumed and perceptions of fullness, hunger, and enjoyment of food in a healthy young-adult population. METHODS: A randomized controlled crossover study of 119 healthy adults (20.2 +/- 1.4 y; 57% women; 48% white) assigned participants to begin under either the distracted (DIS, n = 55) or control (CON, n = 64) conditions. DIS participants consumed a meal of quiche while completing a Rapid Visual Information Processing (RVIP) for 15 min. CON participants ate without any task assignment. After a 30-min rest period, participants were offered a snack and given 5 min to eat ad libitum. Participants completed a survey assessing fullness, hunger, and enjoyment of the meal using 100 mm visual analogue scales. One week later, participants completed the opposite condition. Data were analyzed using ANOVA. RESULTS: Those in DIS consumed 13 g less of the meal (P < 0.001), even when comparing by initial condition (P < 0.001) and adjusting for sex (P < 0.001). A carryover effect of initial condition was found (P < 0.001), such that participants first assigned to DIS condition consumed less (95.2 +/- 61.7 g) when distracted compared to all other condition combinations (127-133 g). Those in DIS had decreased accuracy for both memory of quiche received (absolute difference, 1.1 +/- 1.6 compared with 0.7 +/- 1.2 for CON, P < 0.001) and memory of quiche consumed (0.8 +/- 1.1 for DIS compared with 0.7 +/- 1.2 for CON, P = 0.007). CONCLUSIONS: When distracted, healthy young adults consumed significantly less food and their memory of the meal was dampened. These findings underscore the potential importance of cognitive distraction in affecting food intake. This trial was registered at clinicaltrials.gov as NCT04078607.