By Dr. Shaun Hanson

We've all been there before. You hunker down by the TV with a bag of chips, a tub of ice cream or perhaps your very own pizza pie, and before you know it, the credits are rolling, and the food is gone.

Were those pepperoni slices extraordinarily tasty? Or did the title of that "Hunger Games" movie have a subliminal effect on your appetite? Something made it much easier to eat while you were on that couch, but what exactly?

A new study from the Food and Brand Lab at Cornell University asks that very question. What it finds is that it's not TV itself that makes the cheesy puffs go "poof," but certain shows or movies that may stop you from realizing just how much you're consuming, until it's too late.

The study, published Monday in the journal JAMA Internal Medicine, was led by Aner Tal, a Ph.D. in consumer behavior at Cornell. Tal hypothesized that distracting, action-packed programming was a key factor.

"If I go to the cinema and I'm really engrossed in the movie, I find myself with an empty bucket of popcorn 10 minutes later," Tal said. "In a previous study, people would even eat stale popcorn if they weren't paying attention."

Accordingly, he chose a 20-minute segment from a film that was bound to capture attention: Michael Bay's action movie "The Island." For a less distracting option, he chose an excerpt from the interview program "Charlie Rose."

Tal and his colleagues then recruited three groups of about 30 college students each. One group watched the clip from "The Island," while another group watched the same clip without sound. The third group watched the "Charlie Rose" segment. Meanwhile, these students were supplied with as many M&M's, cookies, carrots and grapes as they liked.

The results? The students who watched the action movie ate nearly twice as much of all the snacks than those watching the comparison show, which had far fewer camera cuts and fluctuations in sound. Even the students who watched the soundless version of the action movie ate more than the control group.

This, Tal said, was a surprise.

"We expected the action movie to get people to eat more than the laid-back talk show," he said. "What had never been shown before is that even without sound, you could still get higher levels of engagement, which is relevant if you think about contexts where TV is on in the background, like at bars and restaurants."

The study's findings also suggested that the flashy film with jarring camerawork had a bigger impact on male subjects than female subjects. Regardless, the students consumed all snacks in increased amounts in the action film group, suggesting that eating was indiscriminate and based on what was close at hand.

Tal clarified, however, that the findings of the study do not necessarily mean that television is inherently harmful.

"It has been associated with increased BMI and sedentary lifestyle, but 'everything in moderation' applies to TV as well as food," he said. "We're also interested in how online content influences consumption. In theory, it should work the same way."

More studies might be needed to confirm these findings, however. Dr. Kelly Pritchett, spokeswoman for the Academy of Nutrition and Dietetics, said this study, while interesting, was not conclusive.

"It's hard to infer what this means for the general population," said Pritchett, who was not involved with the study. "It's just one group. We don't know how this would apply to middle-aged Americans. We also don't know anything about these students, about their families or socioeconomic status."

Doctor's Take

A growing body of evidence suggests that the factors that lead to obesity and unhealthy eating habits have to do with much more than simply what is on our plates. This study is the latest to demonstrate how distractions in our environment can affect our behavior when it comes to food.

"We're trying to help people avoid mindless eating traps," Tal said. "More distracting content is more dangerous."

So what can you do to counter this tendency? Tal says the solutions are simple.

"If you have to snack, you can pour out a reasonable portion and put the rest in the kitchen," he said. "Getting up for more would require conscious engagement. If you have to have endless snacks, instead of chips or candy, you can have baby carrots."

As for those who prefer to settle in for a quiet evening with Charlie Rose, Tal said he did not intend the study to diminish the importance of in-depth talk shows.

"I was constantly thinking about that when I wrote the paper," he said. "If he found out about it, I would have to say, 'nothing personal.'"

Action-packed TV programs may fuel mindless munching, a new study found. (Image credit: Mike Kemp/Getty Images)