BRIGHTON, United Kingdom — Do you ever wonder how that giant bag of popcorn is empty by the end of the movie? A recent study finds snackers have a hard time realizing they’re full and wind up overeating while focusing on other things. Researchers say the more our brains lock in on something, especially watching television, the less it’s able to tell when we should stop eating.
The findings offer a clear strategy when it comes to snacking while watching TV: limit yourself to a healthy portion. Trusting our gut, in this case, to tell us when to stop simply won’t do us any good. And it’s not just television that’s the culprit. Any activity that engages us will take our mind off our appetite, the study shows.
You’re more likely to overeat when your attention isn’t on your food
The study by the University of Sussex examines 120 people, giving them low or high-calorie drinks while completing various perceptually-demanding tasks. The British team reveals activities which require lots of attention trick many participants into overeating, even if their drink was more filling.
Those engaging in highly-demanding tasks ate the same amount of snacks after their test, regardless of having low or high-calorie drinks before eating. Participants doing less-engaging activities however, are able to tell when they’ve had enough snacks.
Researchers report volunteers who had a highly-filling drink while completing a simple task ate 45 percent fewer snacks than their peers who had a low-calorie drink. The University of Sussex says other studies also show the brain filters out sensory information when perceptual demand is high. They add this is the first report to prove nutrient cues and satiety (the feeling of being full) are part of those dropped signals.
“Our study suggests that if you’re eating or drinking while your attention is distracted by a highly engaging task, you’re less likely to be able to tell how full you feel. You’re more likely to keep snacking than if you’d been eating while doing something less engaging,” Professor Martin Yeomans explains in the university release.
Binge watchers and gamers beware
The study has significant health implications, especially for people at risk for obesity or leading inactive lifestyles.
“This is important for anyone wanting to stay a healthy weight: if you’re a habitual TV-watching snacker – watching, say, an engaging thriller or mystery, or a film with a lot of audio or visual effects – you’re not likely to notice when you feel full. Video-gamers and crossword solvers should also take note!” says Yeomans.
“We already knew that feeling full could be affected by the texture and appearance of food, as well as pre-existing expectations about how full we think a type of food should make us feel,” he adds. “Now we also know that feeling full depends on how much sensory information our brains are processing at the time.”
The study appears in the journal Appetite.