Letting kids use a cell phone at dinner seems to be the height of rudeness, symbolic of participation trophy culture and a desire to be best friends with a child rather than a parent, but a new study argues it may be better for health. If it reduces calorie intake.

It's no secret the developed world has an obesity problem, and it is no secret that cell phones are now ubiquitous, but while some try to create a causal link between them, the new paper say phones can be preventative.

 Being distracted by technology during mealtimes may decrease the amount of food a person eats, nutrition scientists suggest in a new study. In the Journal of Nutrition paper, 119 young adults consumed a meal while playing a simple computer game for 15 minutes ate significantly less than when they ate the same meal without distractions. Participants' food consumption was evaluated on two separate occasions - one day when they played the game while eating and on another day when they ate without distractions.


Lead author Carli Liguori. Image: Sarafina Joy Photography

The game, called Rapid Visual Information Processing, tests users' visual sustained attention and working memory and has been used extensively by researchers in evaluating people for problems such as Alzheimer's disease and attention-deficit disorder. It randomly flashes series of digits on the computer screen at the rate of one per second. Participants in the study were instructed to hit the space bar on the keyboard whenever they saw three consecutive odd numbers appear.

"It's fairly simple but distracting enough that you have to really be watching it to make sure that you don't miss a number and are mentally keeping track," said lead author Carli A. Liguori, who recently got a master's degree in food science and human nutrition at the University of Illinois at Urbana-Champaign. "That was a big question for us going into this - how do you ensure that the participant is distracted? And the RVIP was a good solution for that."

The participants, who had fasted for 10 hours before each visit, were told to consume as much as they wanted of 10 miniature quiches while they were either playing the game or eating quietly without distractions for 15 minutes.

The food was weighed and counted before and after it was given to each person.

After a 30-minute rest period, participants completed an exit survey that asked them to recall how many quiches they had been given and the number they had consumed. They also rated how much they enjoyed the meal as well as their feelings of hunger and fullness.

Liguori hypothesized that when people ate while using the computer game they would not only consume more food but would have poorer memory of what they ate and enjoy it less. Instead, she found that participants ate less when they were distracted by the computer game. Moreover, participants' meal memory - their ability to recall how much they had been served and eaten - was less accurate when they were distracted than when they ate quietly without the game.

However, participants' consumption on their second visit was affected by which activity they had performed during their initial visit. The people who engaged in distracted eating on their first visit ate significantly less than their counterparts who did not experience the distracted eating condition until their second visit.

Moreover, when participants who engaged in the distracted eating on their first visit were served the quiches on their next visit, "they behaved as if they were encountering the food for the first time, as evidenced by a lower rate of consumption similar to that of those who began" with the non-distracted meal, according to the study.

The results suggest that there may be a difference between distracted eating and mindless eating. Mindless eating may occur when we eat without intending to do so while distracted eating may occur when we engage in a secondary activity such as watching TV or answering emails while we are deliberately eating. Although the terms are often used interchangeably, they may be distinctly different behaviors with nuances that need to be explored.

There are confounders, of course. These were all college students and the game was not Gardenscapes or a real game, so it may have seemed more like a test and that created more concentration.