If you’ve eaten at a Chili’s, Uno Pizzeria, or Applebee’s in recent years, you might have encountered a touchscreen menu: a tablet from which you can select your order instead of talking to a server. Uno found that installing touchscreen menus in some restaurants pushed their dessert sales up by 30 percent, Planet Money reported last year. “One theory is that customers feel like waiters will judge them if they order dessert right after they’ve eaten a huge pizza,” said reporter Stacey Vanek Smith, whereas a machine won’t judge them.
In a paper soon to be published in the Journal of Marketing Research, a trio of researchers offer an alternate explanation: Using touchscreens to select food makes us feel like we are actually reaching toward that food to grab it, which makes us more likely to select “affect-laden products” (like cheesecake) than “cognitively superior products” (like fruit salad). Hao Shen and Meng Zhang of the Chinese University of Hong Kong and Aradhna Krishna of the University of Michigan found that university students in Hong Kong were more likely to choose hypothetical junk food over hypothetical healthier options when they used a touchscreen than when they used a desktop computer with a mouse. Interestingly, the effect also held when the researchers compared touching a touchscreen to using a stylus on a touchscreen. It was the act of touching the screen that apparently triggered hedonistic choices, rather than the convenience or interface of the touchscreen.
A few caveats are necessary: The studies used a small sample size in each phase of the study, between 85 and 228 students. Some of the students participated for extra credit, and the others were paid the equivalent of $1.30, which means they might not have had much of an incentive to take the study seriously. And the effect of touching the touchscreen was not huge: 95 percent of people using a touchpad selected hypothetical cheesecake over hypothetical fruit salad, but so did 73 percent of people using a desktop computer. Yes, the touchscreen apparently lowered people’s resistance to the cheesecake, but most people were going to choose cheesecake no matter what.
This isn’t the first (or last) study to attempt to tease out how external factors can affect what and how much we eat. Think of all those studies on whether plate size affects consumption, or a recent study showing that people make healthier food choices when they eat under bright lights. These kinds of studies are useful for the food service industry, which can use findings like this to bolster sales of items with a high profit margin. (It’s no coincidence that the researchers behind the touchscreen study are professors of marketing.) These studies are also useful for regulators who want to understand how food manufacturers and vendors exploit consumers’ unconscious weaknesses. They’re also arguably just plain interesting, even if their conclusions ought to be taken with a grain of salt.
But I worry that studies like this play into a larger cultural narrative—one that also gets pushed by the diet industry, often onto women—that people just can’t trust themselves around food, that our instincts will lead us astray. A person who is concerned about his or her eating habits or weight might read about this study and conclude, “Oh god, I won’t be able to control myself if I follow my gut; my intuition is trying to undermine me.” This is the harmful notion that underpins most eating disorders. It’s self-evident that external factors affect what one eats, but that doesn’t mean that eating healthfully requires rigidly counting every calorie so that you don’t fall prey to touchscreens or big plates or dim lighting. People can trust your gut if they eat when they’re hungry, stop eating when they’re full, and pay attention to how different foods make them feel. If you’re not used to eating intuitively, this is really hard, and even scary, at first—but once you get the hang of it, the possibility that a touchscreen might have a small influence on your order won’t freak you out. And neither will the possibility that you might sometimes choose cheesecake over fruit salad.
