Why Technology Makes Us Fat: the Answer Isn't as Simple as You Think

Canada is facing an obesity epidemic. Almost a quarter of Canadians over the age of 30 were classified as obese in 2009, and the numbers have been going up consistently for the last 30 years. And along with them, the rates of heart disease, diabetes, hypertension, and even some forms of cancer.

Much of the research conducted has largely shown the obvious—that increasingly poor nutrition and a lack of physical activity are leading this surge in weight gain.

People are eating more pre-prepared meals than ever before (both of the boxed variety found in supermarkets and at restaurants and fast food locations), and engaging in lifestyles that are increasingly sedentary, both due to changes in the job market that have more of us sitting at desks for eight to 12 hours a day and because of changes in how we spend our leisure time.

But a 2007 Statistics Canada study brought in a related factor and uncovered many things that were quite interesting. This research paper focused solely on how our sedentary lifestyles were affecting our waistlines, and pointed the finger right at technology—specifically at how much time we spend sitting in front of screens.

Many of their findings seem relatively expected at first glance.

• 15% of Canadian adults are frequent computer users in their leisure time (more than 11 hours each week).

• Three in 10 Canadian adults are frequent television watchers (more than 15 hours each week).

• One in Five Canadian adults watch TV 21 or more hours every week.

• 5% of Canadian adults are both frequent TV watchers and frequent leisure time computer users.

• Computer use is replacing television use among the younger people surveyed, with almost half of the screen hours reported by 20- to 24-year-olds being on a computer.

• Younger and more highly-educated people are using computers more and watching TV less; this is also true for recent immigrants.

• How much you watch the TV and use the computer have a strong correlation with your level of obesity.

• People who reported watching 21 or more hours of TV a week (at least three hours a day!) were almost twice as likely to be obese as those watching five hours or less each week.

• “Screen time” maintained its connection to obesity regardless of other potentially influencing factors such as education, age, whether the people lived in an urban or rural environment, and the person’s household income.

None of that seems particularly surprising. Just from looking at weight gain logically, you would expect that people engaged in more sedentary activities like watching TV shows and playing around on their computers would have a higher likelihood of being obese.

But here’s where the study really gets interesting: people who engage in a lot of leisure reading, another supposedly sedentary activity, do not show the same increased risks of obesity as those enjoying a lot of “screen time,” even when their relative nutrition and physical activity outside of these activities are similar.

One of the authors of the study, Margot Shields, goes on to say that even when the factors of diet and exercise were controlled in a general sense, the study still found a strong correlation between obesity and “screen time.” Essentially, stare at a monitor during a lot of your free time—any monitor, apparently—and you’ll have a higher likelihood of being overweight or obese.

How could that be?

It seems crazy, but it begs the question whether there might actually be something about the technology behind screens themselves that encourages weight gain. The authors of the study argue that more needs to be done to research the meaning behind “physically active,” and it’s hard to disagree. After all, while most people intuitively understand that you expend more metabolic energy cleaning the house or even playing card games than you do sitting at the computer or in front of the TV, it’s far more surprising that reading doesn’t correlate to obesity in the same way.

For a society becoming increasingly dependent on screen-based leisure activities of all kinds—games, internet surfing, social media, and videos of all kinds—research like this is only going to become more important as time goes on.