HOUSTON - The size of a person's waistline may be linked to mobile phones, tablets and laptops, according to a recent study led by Rice University in Houston.
Scientists noticed a trend that correlates with the rise of technology in society. As digital devices became more prevalent, people got fatter. Obesity around the world has tripled since 1975, according to the World Health Organization.
While changes in people's food intake and activity levels have been attributed to the trend, Rice University post doctoral fellow Richard Lopez wondered if there is a link between weight gain and the mindless multitasking on various digital devices, which has nothing to do with a sedentary lifestyle.
"When we talk about media multitasking here, we're not talking about effectively multitasking where you're monitoring one thing and you're doing another and you're able to succeed at both. It's kind of this mindless switching that we believe is relatively involuntary, like I was looking at Instagram or Twitter. Where did the time go?"
Lopez, along with researchers from Dartmouth University and Ohio State University, conducted a study where 132 university-age adults from 18 to 23 years old answered questions such as how often are they were distracted by notifications on their phone. Researchers also measured participants' body fat.
"We found that those who reported multitasking more frequently with their devices had (a) higher risk for obesity as measured by BMI (body mass index) and percent body fat," said Lopez, who also was trained in cognitive neuroscience and psychology.
Then, 72 of the participants underwent brain imaging while being shown various unrelated images, including fatty foods. The study found that those who media multitasked more, when exposed to tempting food cues, showed different patterns of brain activity.
"We found a relationship whereby those who are high media multitasking had more reward-related activity in those brain systems that drive eating behavior (and) less activity in other prefrontal regions that help with self-control."
Lopez continued, "I would not be surprised, I'll say, if (a) high media multitasker also struggle(s) with other temptations in other domains."
Media multitasking refers to "the extent to which people mindlessly use and switch between unrelated devices," such as looking at a laptop and then checking a smartphone.
Researchers do not know whether people who tend to multitask with digital devices lack self-control, and as a result, their brain development is affected, or whether people with specific patterns of brain development have a tendency to multitask with their devices.
Lopez said the next step is to conduct more studies that track people over time to see whether obesity drives mindless multitasking with digital devices, or whether people who switch between devices become obese over time.