Eating while watching TV or playing on your computer might seem like a fun and efficient way to both feast your eyes and fill your stomach. But a new study shows that people who do this often lose track of what they eat and overindulge.
Researchers assessed the effect of eating while playing a computer game. Participants were split into two groups. One group ate a lunch comprised of nine different foods while playing Solitaire – a computerized card-sorting game. The second group ate the same lunch, but without distraction.
The researchers found that participants who played Solitaire felt less full after lunch. Moreover, the effects of distraction were long lasting. Thirty minutes later, the distracted participants ate around twice as many snacks as did non-distracted participants.
Finally, at the end of the test session, the participants tried to remember the food items that they had been given for lunch. Distracted participants had a poorer memory.
Together, these findings highlight an important role for memory of recent eating and reveal that distraction can lead to increased food intake later in the day.
Previously, similar observations have been made in people who eat while watching TV. This study extends these findings by showing how other "screen-time activities" can influence our food intake in unexpected ways.
This is important, the researchers said, because it reveals another mechanism by which sedentary screen-time activities might promote obesity.
"This work adds to mounting evidence from our lab and others that cognition, and memory and attention in particular play a role in governing appetite and meal size in humans," said Jeff Brunstrom of the experimental psychology department at the University of Bristol in the UK and one of the study co-authors.
The research is published in the January issue of the American Journal of Clinical Nutrition.